Ramnath is such a sham that it is difficult to get along with him.

Answer: Option A

Pretender : a person who claims or aspires to a title or position.
Unnatural : contrary to the ordinary course of nature; abnormal.
Blunt : (of a cutting implement) not having a sharp edge or point.
Farcical : relating to or resembling farce, especially because of absurd or ridiculous aspects.
Sham : a person who pretends to be someone or something they are not.

Synonym of Sham is Pretender