From the words lettered A to D below each of the following sentences, choose the word or group of words as it is used in the sentence I don't believe that a...

Answer Details

The correct word to complete the sentence is "mature". The sentence is expressing disbelief that someone with a certain characteristic would do something. "Matured" means that someone has developed or grown in maturity, which is not the intended meaning of the sentence. "Maturing" refers to the process of developing or growing in maturity, and "matures" is the present tense of the verb "mature", which is not appropriate in this sentence. Therefore, "mature" is the best option as it refers to a person who has already developed and possesses maturity.