Final answer:
The correct form of the pronoun in parentheses is 'Theirs'.
Step-by-step explanation:
Theirs is the longest driveway.
The correct form of the pronoun in parentheses is Theirs.
The pronoun 'Theirs' is a possessive pronoun, used to show ownership. In the given sentence, 'Theirs' is used to indicate that the longest driveway belongs to someone or a group of people.
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