Twenty men fell into the water and were _____ by other boats. As a result, they missed the fighting on the beach.

A．picked out

B．picked over

C．picked up

D．picked on

班杜拉社会学习理论的核心概念是（ ）

A．经典条件反射

B．操作条件反射

C．联结

D．观察学习