Is it appropriate work conversation to be asked by the owner of where you work what your type in guys is ?

Red flag, not appropriate for anyone in you job, let alone the boss to ask that question.

No it's not. One way to respond to inappropriate comments is questions is "I'm not understanding you. You can't mean what it sounded like you meant. Is this something important?" Letting the other person off with "It was a misunderstanding and it isn't important" avoids the awkwardness of pointing out that it's inappropriate. 

But there may be times when sidestepping what is inappropriate isn't your best course. There may be times when a loud and clear "How DARE you!" is a better option. You're there so, you make the call on how to play it.

Be careful around this boss in the future. Don't be alone with him. Don't get without grabbing distance. Don't dress flirty and don't act flirty, not with him and not with anybody else either. Be strictly professional, strictly business, no fun. And keep records of anything else that happens including when, where, any witnesses, and what was said or done.  

No it is not appropriate work conversation.  NO questions of a personal nature are appropriate, although often they are asked.  But definitely, those of a sexual/dating content are NOT appropriate.

And the appropriate response should be, "That is not an appropriate question to ask of an employee".

Not really, but the smaller the company the blurrier the lines can get irl.  The lower down the pecking order you are the more uncomfortable that question can be.  If you're next in charge you're just shooting the breeze.  Teenage new hire and it's straight up wrong.

No - that is way out of bounds