下列用户口令安全性最高的是（）。

A.19801212

B.Zhangsan

C.Zhang!san10b

D.Zhangsan1980

Remember, my children. __________ you work, __________ result you will get.[ ]

A. The harder; the better

B. The better; the harder

C. The hard; the better

D. The harder; the good