The correct answer is D. Mary said that she is sorry.
Option A is incorrect because it uses the past tense, while the sentence in the prompt uses the present tense. Option B is incorrect because it uses the future tense, while the sentence in the prompt does not specify when Mary will be sorry. Option C is incorrect because it uses the present tense, but the sentence in the prompt uses the direct quote “I am sorry,” which indicates that Mary is speaking in the first person.
The sentence “Mary said, ‘I am sorry'” is a direct quote. Direct quotes are used to reproduce the exact words that someone said. In this case, Mary is saying that she is sorry. This could be because she has done something wrong, or because she is feeling regret or remorse.