he use to visit us every week, but ----- now?
he use to visit us every week, but ----- now?
Explanation
he use to visit us every week but rarely comes now.
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The sentence is in the simple present tense with a singular subject.
"Rarely comes" in option A is correct as it indicates the singular verb for the singular subject 'He'. The verb is also in tense agreement with the sentence as both are in the simple present tense.