统计推断包括（）

A.统计描述和假设检验

B.参数估计和假设检验

C.统计描述和统计分析

D.点估计和区间估计

E.计算出均数和标准差

Taking care of children calls for your time, abilities, patience and emotions. _____, it is not a simple thing.

A．On the contrary

B．What's more

C．In conclusion

D．On the other hand