I think you should carefully word your enquiry, and without being agressive (i.e. attacking his teachingn style), you should try to find out why he thinks this is a question which has a 'right' answer. Maybe something like:
"I was pleased with my grade, but I am a little confused about the question. What did you mean when you said that this question has a certain 'right' answer?"
Then if he says something evasive like "the facility does not belong in a residential area", which isn't answering what you asked, just restating his opinion, then clarify with:
"Yes, but why does this question have a certain 'right' answer, surely this is an open question, there are many ways of approaching it, and they don't all lead to the same place."
If you can't come to an understanding of this with him, I'd say keep with your instincts. I've always done this in the past on things like this, and it has cost me occasionally, but at least I still have my integrity. On the other hand, this isn't your integrity on any major level, and the grades might be very valuble.
Another arguement for answering your own way is this: I had a friend doing an English degree and his teacher had this crazy thing about everything somehow involving phallic symbols. This teacher was obviously a great believer in Freud. An essay submitted which didn't revolve around this topic, did not do very well. So my friend dutifully wrote out an essay (which counted towards his final mark) which did revolve around phallic symbols. And then his teacher changed, so the essay was marked by someone else, who recognised it as being not very good. My friend was asked to explain his essay, and he couldn't really do it, and he recieved a bad grade.
So at least you can defend your ideas, whereas if you write your professors and then someone else marks it and asked you what the hell you were talking about, you'll be stuck.