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Question 1. Which HTTP status code indicates that the request was successful and a new resource was created? A) 200 OK B) 201 Created C) 400 Bad Request D) 404 Not Found Answer: B Explanation: 201 Created is returned when a request (typically POST) results in the creation of a new resource on the server. Question 2. In Java, which keyword is used to inherit from a superclass? A) implements B) extends C) inherits D) super Answer: B Explanation: The extends keyword establishes an inheritance relationship between a subclass and its superclass. Question 3. What is the time complexity of binary search on a sorted array of size n? A) O(n) B) O(log n) C) O(n log n) D) O(1) Answer: B Explanation: Binary search repeatedly halves the search interval, yielding logarithmic time complexity. Question 4. Which of the following SQL clauses is used to remove duplicate rows from a result set?
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A) DISTINCT
B) UNIQUE
C) GROUP BY
D) HAVING
Answer: A Explanation: The DISTINCT keyword filters out duplicate rows in the SELECT output. Question 5. In JavaScript, which method creates a shallow copy of an array? A) slice() B) splice() C) copy() D) clone() Answer: A Explanation: Array.prototype.slice() without arguments returns a shallow copy of the original array. Question 6. Which of the following is NOT a characteristic of the Agile SDLC model? A) Fixed scope from the start B) Iterative development C) Continuous stakeholder feedback D) Adaptive planning Answer: A Explanation: Agile embraces changing requirements; a fixed scope contradicts its core principles. Question 7. In object-oriented programming, which principle is best described by “hide internal implementation and expose only what is necessary”? A) Polymorphism
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D) Tree Answer: B Explanation: A stack adds and removes elements from the same end, making the most recent element the first to be removed. Question 11. In Git, which command stages changes for the next commit? A) git commit B) git push C) git add D) git merge Answer: C Explanation: git add moves file modifications from the working directory to the staging area. Question 12. Which of the following is a NoSQL database type that stores data as JSON-like documents? A) MySQL B) PostgreSQL C) MongoDB D) Oracle Answer: C Explanation: MongoDB is a document-oriented NoSQL database that uses BSON (binary JSON) for storage. Question 13. In Java, which exception type must be either caught or declared in the method signature? A) RuntimeException B) Error C) Checked exception D) Unchecked exception
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Answer: C Explanation: Checked exceptions are verified at compile time; the compiler forces handling or declaration. Question 14. What does the Big-O notation O(n²) represent? A) Linear growth with input size B) Quadratic growth with input size C) Constant time operation D) Logarithmic growth Answer: B Explanation: O(n²) indicates that the algorithm’s running time grows proportionally to the square of the input size. Question 15. Which HTML5 element is used to embed video content? A) B) C) D) Answer: B Explanation: The `` tag provides native support for video playback in browsers. Question 16. In a relational database, what is the purpose of the PRIMARY KEY constraint? A) To allow duplicate rows B) To enforce referential integrity C) To uniquely identify each row D) To sort the table automatically Answer: C
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Explanation: RESTful APIs leverage HTTP verbs (GET, POST, etc.) and can exchange data in JSON or XML. Question 20. In JavaScript, what does the Promise object represent? A) A synchronous function return value B) A placeholder for a value that may be available later C) An error handling mechanism only D) A way to create loops Answer: B Explanation: A Promise encapsulates an eventual value from an asynchronous operation, allowing then/catch handling. Question 21. Which data structure is best suited for implementing a FIFO (First-In-First-Out) queue? A) ArrayList B) Stack C) LinkedList D) HashMap Answer: C Explanation: A LinkedList can efficiently add at the tail and remove from the head, matching FIFO behavior. Question 22. What is the purpose of the finally block in a try-catch-finally construct? A) To execute code only when an exception occurs B) To execute code only when no exception occurs C) To execute code regardless of whether an exception was thrown D) To re-throw the caught exception Answer: C
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Explanation: The finally block runs after try and catch blocks, irrespective of exception occurrence. Question 23. Which of the following is a characteristic of the Waterfall software development model? A) Overlapping phases B) Iterative feedback loops C) Sequential, non-iterative phases D) Continuous delivery Answer: C Explanation: Waterfall follows a linear sequence where each phase must be completed before the next begins. Question 24. In SQL, which clause is used to filter groups after aggregation? A) WHERE B) HAVING C) ORDER BY D) LIMIT Answer: B Explanation: HAVING applies conditions to aggregated results, while WHERE filters rows before aggregation. Question 25. Which Java keyword is used to prevent a class from being subclassed? A) static B) final C) abstract D) sealed Answer: B Explanation: Declaring a class as final disallows inheritance.
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A) Defining multiple methods with the same name B) Hiding internal data and exposing a public interface C) Creating a hierarchy of classes D) Allowing objects to take many forms Answer: B Explanation: Encapsulation restricts direct access to object data, providing controlled interaction via methods. Question 30. In JavaScript, what does the === operator test? A) Equality after type coercion B) Strict equality without type coercion C. Assignment of values D. Inequality Answer: B Explanation: === checks both value and type, ensuring strict equality. Question 31. Which of the following is a key benefit of using version control systems like Git? A) Automatic code optimization B) Real-time debugging C) Tracking changes and collaborative development D) Faster compilation Answer: C Explanation: Git records history, enables branching/merging, and facilitates teamwork. Question 32. In a relational database, what does the term “normalization” aim to achieve? A) Increase data redundancy B) Reduce data integrity
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C) Eliminate update anomalies and redundancy D) Simplify query syntax Answer: C Explanation: Normalization structures tables to minimize duplication and maintain consistency. Question 33. Which of the following is an example of a spatial visualization question often found in aptitude tests? A) Solving a quadratic equation B) Interpreting a line chart C) Rotating a 3-D object mentally D) Finding the next number in a series Answer: C Explanation: Spatial visualization assesses the ability to manipulate shapes mentally, such as rotating a 3-D figure. Question 34. Which Java keyword is used to define a method that does not return a value? A) void B) null C) return D) static Answer: A Explanation: void indicates that a method performs actions but does not produce a return value. Question 35. In CSS, which selector targets all <p> elements that are direct children of a </p>? A) div p B) div > p
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D) Scenario, Theory, Answer, Reason Answer: A Explanation: STAR provides a structured way to answer competency questions by describing the Situation, Task, Action, and Result. Question 39. In Java, which interface must a class implement to be used in a try-with-resources statement? A) Closeable B) Serializable C) Runnable D) Comparable Answer: A Explanation: try-with-resources automatically closes objects that implement java.io.Closeable (or AutoCloseable). Question 40. Which cloud service model provides a platform allowing customers to develop, run, and manage applications without managing underlying infrastructure? A) IaaS B) PaaS C) SaaS D) DaaS Answer: B Explanation: Platform-as-a-Service (PaaS) supplies runtime environments, databases, and development tools while abstracting server management. Question 41. Which of the following is a characteristic of a singly linked list? A) Each node points to both previous and next nodes B) Random access to elements in O(1) time C) Traversal only possible in one direction
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D) Fixed size after creation Answer: C Explanation: In a singly linked list, each node contains a reference to the next node only, allowing one-way traversal. Question 42. What does the git merge command do? A) Deletes a branch B) Incorporates changes from one branch into another C) Shows commit history D) Rewrites commit messages Answer: B Explanation: git merge combines the histories of two branches, integrating changes. Question 43. In JavaScript, which of the following is a true statement about arrow functions? A) They have their own this binding B) They can be used as constructors with new C) They do not have a prototype property D) They support the arguments object Answer: C Explanation: Arrow functions lack a prototype and cannot be used with new; they also inherit this from the surrounding scope. Question 44. Which SQL command is used to remove a table and all its data permanently? A) DELETE TABLE B) DROP TABLE C) TRUNCATE TABLE D) REMOVE TABLE
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Explanation: Queues remove the oldest element first (FIFO), while stacks remove the most recent (LIFO). **Question 48. In a relational database, what does the term “foreign key” refer to? ** A) A key that uniquely identifies a row in its own table B) A key that references the primary key of another table C) A key that is automatically generated by the DBMS D) A key that cannot contain NULL values Answer: B Explanation: A foreign key enforces referential integrity by linking to a primary key in a related table. **Question 49. Which of the following best describes a “microservice” architecture? ** A) A monolithic application with a single codebase B) A set of small, independently deployable services communicating over APIs C) An architecture where all logic resides on the client side D) A system that uses only one programming language throughout Answer: B Explanation: Microservices break functionality into loosely coupled services that interact via network calls. Question 50. Which JavaScript method is used to convert a JSON string into a JavaScript object? A) JSON.parse() B) JSON.stringify() C) JSON.convert() D) JSON.objectify() Answer: A
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Explanation: JSON.parse() parses a JSON-formatted string and returns the corresponding object. Question 51. In a relational database, which normal form eliminates transitive dependencies? A) 1NF B) 2NF C) 3NF D) BCNF Answer: C Explanation: Third Normal Form (3NF) removes transitive dependencies, ensuring that non-key attributes depend only on primary keys. Question 52. Which of the following is a primary advantage of using interfaces in Java? A) They allow multiple inheritance of implementation B) They provide default method bodies only C) They define a contract that multiple classes can implement D) They store state data for objects Answer: C Explanation: Interfaces specify method signatures that implementing classes must fulfill, enabling polymorphic behavior. Question 53. Which of the following statements about ArrayDeque in Java is true? A) It is thread-safe by default B) It can be used as both a stack and a queue C) It does not allow null elements D) Both B and C are correct Answer: D
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Explanation: The daily stand-up is a brief meeting for team members to share what they did, plan to do, and any impediments. Question 57. Which of the following statements about the final keyword when applied to a method is correct? A) The method can be overridden in subclasses B) The method cannot be overridden in subclasses C) The method becomes static automatically D) The method must be abstract Answer: B Explanation: Declaring a method as final prevents subclasses from overriding it. **Question 58. Which of the following is a valid way to declare a constant in Python? ** A) const PI = 3. B) #define PI 3. C) PI = 3.14 # by convention, uppercase name indicates constant D) final PI = 3. Answer: C Explanation: Python does not enforce constants; using uppercase naming signals intent to treat the variable as constant. Question 59. In SQL, what does the LIKE operator do? A) Performs exact match comparison B) Searches for a pattern using wildcards C) Joins two tables D) Orders the result set Answer: B Explanation: LIKE allows pattern matching with % (any sequence) and _ (single character) wildcards.
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Question 60. Which of the following is an advantage of using a HashMap over a TreeMap in Java? A) Guarantees sorted order of keys B) Provides O(log n) lookup time C) Offers average O(1) lookup time D) Maintains insertion order Answer: C Explanation: HashMap offers constant-time average performance for get/put, whereas TreeMap provides sorted order with O(log n) operations. **Question 61. Which of these is a correct way to declare an abstract class in Java? ** A) abstract class Vehicle { } B) class abstract Vehicle { } C) public abstract Vehicle { } D) abstract public class Vehicle { } Answer: A Explanation: The abstract keyword precedes the class declaration; public can be added but is not required for the example. Question 62. In JavaScript, which method removes the last element from an array and returns it? A) pop() B) shift() C) splice() D) slice() Answer: A Explanation: Array.prototype.pop() removes and returns the array’s last element.
