An earthquake hit the hometown of one of your friends, Xiao Wang, a week ago. Write a letter to condole with him on the disaster and offer help to him.
Do not sign your own name at the end of the letter. Use "Li Ming" instead.
Do not write the address.

挫折-侵犯理论认为，侵犯强度同目标受阻强度之间是（）的关系。

A.正相关

B.负相关

C.无关

D.很复杂