Consider the context-free grammar G below for arithmetic expressions :…

2023

1. A.

   The string "id +id×id " has no parse tree according to G

2. B.

   The string "id +id× id" has only one parse tree according to G

3. C.

   The string "id +id×id " has exactly two parse trees according to G

4. D.

   The string "id +id×id " has more than two parse trees according to G

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Correct answer: C

The given grammar E→E+E|E×E|id is ambiguous. For the string 'id + id × id', there are two distinct parse trees: one grouping as (id+id)×id and another as id+(id×id). Since multiple parse trees exist for the same string, the grammar is ambiguous.