Which verb agrees with the subject in the sentence?
jeff or carol have an extra pair of skates?
a.
don't
b.
does
c.
do

The verb that agrees with the subject in the sentence is option C. Does. So the complete sentence would be, "Does Jeff or Carol have an extra pair of skates?" We used the singular auxiliary verb "does" because the compound subject "Jeff OR Carol" is connected by the word "or". It is a rule that when subjects are linked by the word "or", it should always take the singular verb. 

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