I didn't interview with an A on hand at the time, but this question keeps popping up and my mentor on an adcom definitely got frustrated with it when she was conducting interviews at our school (not SHSUCOM) this semester. I think you're more than capable of explaining your preference for SHSU without mentioning other schools, especially other acceptances. As far as they're concerned, they already know you're qualified because they chose you for an interview so just continue proving to them "why" SHSU not "why not" school X (plus, your interviewer very well could've gone to/worked at/know people at school X and take offense to any implication that school X has whatever deficiencies you allude to in your answer if you don't word it correctly).