I wish I _____ those words. But now it's too late.a.not having saidb.have never saidc.never saidd.had never said

The correct answer is d. "had never said".

This is because the sentence is talking about a past event that the speaker wishes had happened differently. In English, we use the past perfect (had + past participle) to talk about these kinds of situations.

Here's the step by step reasoning:

a. "not having said" - This is incorrect because "wish" is followed by a clause in the past perfect tense when we want to express a regret about the past.

b. "have never said" - This is incorrect because "have never said" is present perfect tense, which is used to talk about actions that happened at an unspecified time before now. The sentence is talking about a specific past event, so we need to use past perfect tense.

c. "never said" - This is incorrect because "never said" is simple past tense, which is used to talk about completed actions in the past. The sentence is expressing a regret about the past, so we need to use past perfect tense.

d. "had never said" - This is correct because "had never said" is past perfect tense, which is used to talk about actions that happened before another action in the past. In this case, the speaker wishes that they had never said those words before the present moment.