I recently resigned from my last job due to bullying/hostile working environment.?

A different way to put it would be, "didn't like or didn't fit in with the company culture." I don't think there's anything wrong with being honest, but it is usually a bad idea to talk bad about your previous employers. If they ask during the interview, just be brief, and I don't think it would be a good idea to lay blame or complain, unless you can talk positively about the things you tried to do to make the situation better.