In which sentence does the verb agree with the subject?
a. either strawberries or an apple are a healthful choice for a snack.
b. either the cantaloupe or the watermelon is ripe enough to eat.
c. both peaches and plums was on sale at the grocery store.

Either strawberries or an apple are a healthful choice for a snack.  

Verbs are simply known as the ‘action’ words – may it be mental, physical or mechanical. When verbs are paired with auxiliaries (helping verbs), they are known as verb phrase. These helping verbs always go first before the actual verb. Perfect tenses serves a portraying the verb or the action word as something that already happened or is completed, thus the term ‘perfect’. If it is present perfect tense, it means that the action was already done relatively to the present (has/have with past participle). If it is past perfect tense, action is already finished relatively to the past (had with past participle and if it is future perfect tense, action is complete relatively to the future (will have with past participle