The last paragraph is mainly written to______.A．prove that children aren" t as hard as we

The last paragraph is mainly written to______.

A．prove that children aren" t as hard as we imagine

B．prove that adults can learn a lot from children

C．show that children enjoy playing with adults

D．show that our efforts on children are rewarding

请帮忙给出正确答案和分析，谢谢！