GATE DA 2025 Set 1 — Question 23

MCQ+1 / -0.33EasyListsData Types & Control StatementsProgramming, Data Structures & Algorithms

Programming, Data Structures & Algorithms → Data Types & Control Statements → Lists

Last updated 5 September 2026

Question

Consider the following Python declarations of two lists. A=[1,2,3] B=[4,5,6] Which one of the following statements results in A= [1, 2, 3, 4, 5, 6] ?

Correct answer (A) A.extend(B) Solution A.extend(B) iterates over B and appends each element to A . Result: [1, 2, 3, 4, 5, 6] . This is the correct behavior. A.append(B) adds the entire list B as a single element at the end of A . Result: [1, 2, 3, [4, 5, 6]] . A.update(B) is not a valid method for Python lists (it is used for sets and dictionaries). A.insert(B) is invalid syntax; insert requires two arguments: an index and an object. Turn this into a strength. Explore AI-powered practice and doubt support with Success Tracker.

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Correct answer (A) A.extend(B) Solution A.extend(B) iterates over B and appends each element to A . Result: [1, 2, 3, 4, 5, 6] . This is the correct behavior. A.append(B) adds the entire list B as a single element at the end of A . Result: [1, 2, 3, [4, 5, 6]] . A.update(B) is not a valid method for Python lists (it is used for sets and dictionaries). A.insert(B) is invalid syntax; insert requires two arguments: an index and an object.

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