I don’t believe what you said.It is not like her father,who is an honest man,_______ anyone in

B.
"who is an honest man" 可以当做插入语来看待,去掉不影响原句语义.这样原句就成了“It is not like her father to cheat anyone in business.”他爸不像是会在生意上骗大家的人.
It is not like somebody to do something.就是某人不像是会做某事的样子；某事不像是某人做的,这样的意思.
有首歌“what you don't know”里就有一句话“It is not like me to hide behind the wall”