—Look! Miss Mu is on the other side of the street.

—It _____ be her. She's gone to Tibet.[ ]

A. mustn't

B. shouldn't

C. won't

D. can't

陶行知担任育才小学校长时“四颗糖”处理了学生王友用泥块砸自己的同学的事情，该案例体现了陶行知什么样的教学理念（）

A.为人师表

B.关爱学生

C.严慈相济

D.博学善诱