From the words lettered A to D, choose the word or group of words that best completes the sentence. One of the pupils.....able to answer the question correc...

From the words lettered A to D, choose the word or group of words that best completes the sentence.
One of the pupils.....able to answer the question correctly.

Answer Details

The correct option is "was". The sentence is in the past tense and "one" refers to a single person, so the correct verb form to use is the past singular "was".