The correct option is C Future time
Options A and C: In the given sentence, the speaker suggests that 'they' should wait till 'he' comes. This means that, he has not yet come. This sounds like the future tense. The future tense refers to an action that is yet to happen. The person 'he' is yet to come. Hence option C is correct.
Even though 'comes' is in simple present tense, the meaning changes because of the addition of the word 'till'. Often, a simple present verb is used to indicate a future action. For example, 'the train leaves at 6 o'clock'. Hence option A is incorrect.
Option B: Since the action has not yet happened, it cannot be in the past. Thus option B is incorrect.
Option D is incorrect as the answer lies in C.