Rapport grows when students experience the teacher as approachable and supportive.
Why C is marked: Guiding students through learning and difficulties can build trust and constructive communication.
Why A and B are weaker: Authority or displays of knowledge alone do not ensure a trusting relationship.
Question-quality note: Option D, becoming a friend to students, can also suggest rapport, although professional boundaries must remain clear. The choices overlap and should be rewritten for one unambiguous answer.