The correct answer is A.
The sentence “I said, ‘I came here yesterday'” is in the past tense. This means that the speaker is talking about something that happened in the past. In this case, the speaker is saying that they came to the place where they are currently speaking from yesterday.
Option B is incorrect because the speaker is not saying that they are going to the place where they are currently speaking from. They are saying that they came there yesterday.
Option C is incorrect because the speaker is not saying that they had come to the place where they are currently speaking from before. They are saying that they came there yesterday.
Option D is incorrect because the speaker is not saying that they are going to the place where they are currently speaking from. They are saying that they came there yesterday.