What Is the Implicit Premise in the Following Argument

Multiple Choice

What is the implicit premise in the following argument?
Argument: Same-sex marriage is contrary to tradition.Therefore,it should never be allowed.

A) Same-sex marriage is harmful to society.
B) Same-sex marriage is unnatural and therefore should be banned.
C) Whatever causes harm to children should not be allowed.
D) Whatever is contrary to tradition should not be allowed.