A teacher's belief that he or she can reach even the most difficult students and help them learn is called:

A teacher's belief that he or she can reach and help even the most difficult students is called the teacher's sense of efficacy.

Teacher's knowledge (A) is command of subject matter, not a belief about reach.

Teacher's understanding (B) is a grasp of learners or content, not the efficacy belief.

Teacher's self-perception (D) is the general self-image, broader than efficacy.

Teacher efficacy predicts persistence, effort and willingness to try new methods.

The concept grows from Bandura's idea of self-efficacy, the belief in one's capability to succeed.