MCQ Collection
China MCQs
Practice China questions with answers and explanations.
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Correct Answer: B. A primary key uniquely identifies each row in a table
Explanation:
Primary-key values are unique and support reliable row identification and relationships.
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Correct Answer: C. Encapsulation groups data with methods and controls access to internal state
Explanation:
Encapsulation supports modular design by hiding implementation details behind a defined interface.
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Correct Answer: B. Testing seeks evidence about defects and behaviour but cannot prove the complete absence of defects
Explanation:
Testing samples behaviour against expectations; exhaustive proof is usually infeasible.
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Correct Answer: A. A data type constrains the values and operations valid for a variable
Explanation:
Types define representation and permitted operations, helping programs detect invalid use.
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Correct Answer: B. Selection chooses among paths while iteration repeats a block under a condition
Explanation:
Branches choose execution paths; loops repeat work while their control condition allows it.
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Correct Answer: A. Big-O notation describes how resource use grows with input size
Explanation:
Asymptotic notation characterises growth rates rather than exact machine-specific time.
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Correct Answer: A. A primary key uniquely identifies each row in a table
Explanation:
Primary-key values are unique and support reliable row identification and relationships.
Choose an option to check your answer.
Correct Answer: B. Encapsulation groups data with methods and controls access to internal state
Explanation:
Encapsulation supports modular design by hiding implementation details behind a defined interface.
Choose an option to check your answer.
Correct Answer: D. Testing seeks evidence about defects and behaviour but cannot prove the complete absence of defects
Explanation:
Testing samples behaviour against expectations; exhaustive proof is usually infeasible.
Choose an option to check your answer.
Correct Answer: B. A data type constrains the values and operations valid for a variable
Explanation:
Types define representation and permitted operations, helping programs detect invalid use.
Choose an option to check your answer.
Correct Answer: C. Selection chooses among paths while iteration repeats a block under a condition
Explanation:
Branches choose execution paths; loops repeat work while their control condition allows it.
Choose an option to check your answer.
Correct Answer: C. A function packages reusable behaviour and parameters supply inputs to that behaviour
Explanation:
Functions support abstraction and reuse, while parameters pass values into a call.
