The correct answer is D. The teacher requested me not to hesitate in clearing my doubts.
The teacher is using a polite request to encourage the student to clear their doubts. The teacher is not ordering or commanding the student to do anything, but is simply asking them to do so. The teacher is also not warning the student about any consequences of not clearing their doubts, but is simply expressing their desire for the student to do so.
The other options are incorrect because they do not accurately reflect the tone of the teacher’s statement. Option A suggests that the teacher is warning the student, while option B suggests that the teacher is ordering the student. Option C suggests that the teacher is persuading the student, but this is not the case. The teacher is simply making a polite request.