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Which of the following grammars is (are) ambiguous? (A) s → ss | asb | bsa | (B) s → asbs | bsas | λ (C) s → aAB A → bBb B →  A | λ where λ denotes empty string Choose the correct answer from the options given below:

Which of the following grammars is (are) ambiguous? (A) s → ss | asb | bsa | (B) s → asbs | bsas | λ (C) s → aAB A → bBb B →  A | λ where λ denotes empty string Choose the correct answer from the options given below: Correct Answer (A) (B) and (C)

The correct answer is option 4.

Key Points

A is ambiguous because λ can be generated using leftmost derivation having two different parse trees with an empty string.

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B is ambiguous grammar with string abab.

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C is an ambiguous grammar with string abbbb.

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∴ Hence the correct answer is (A) (B) and (C).

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