So um there's a growing debate whether or not to make a law to penalize the LGBT community here in my country and it's becoming a less taboo thing to talk about ever since the US same-sex marriage ruling (USA its impact). And although more and more people are becoming open and become accepting of it, (there are even several activist groups and support groups in some universities, which is then disbanded by the government), there are also those bigoted people who are crying to this and demand a law. They always use the same argument "If homosexuality is right, why is incest and zoophilia wrong? That' almost as ****ed up as those things. So immoral and unnatural. We have to protect our children from this error".
As a LGBT supporter and a bisexual myself, what would you recommend for me and my fellow LGBT activists to be the best answer to these arguments? Even the teachers at my school are spreading homophobia in class like I actually want to argue with them but can't because I'll be damned to do so.

(Sorry for my grammar, not my 1st language)