I feel deep down that it is none of their business unless it would affect your work output. I mean I wouldn't want as a business owner of a welding employee wearing hose and heels. First I would ask what your job description would be and do research as to what that entails. Will you have to wear a uniform or is it an office job where you might set all day.
On the the other hand if it doesn't affect your work output then I would think most bosses could care less.
As said here already I haven't seen that on an application in the states here and really surprised also it's on one in Canada but maybe they are having to hire so many LGBT to prevent law suits or something.