Consider the two grammars: G₁: S → SbS | a G₂: S → aB | ab, A → AAB | a, B → ABb | b Which of the following options is correct?

1. AOnly G₁ is ambiguous
2. BOnly G₂ is ambiguous
3. CBoth G₁ and G₂ are ambiguous
4. DBoth G₁ and G₂ are not ambiguous

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Correct answer: C. Both G₁ and G₂ are ambiguous

Explanation

In G₁, ababa has two parse trees (group left or right). In G₂, ab comes from S → ab directly and from S → aB → ab. Both are ambiguous.