I was honest, like Chemguy said.
It comes up any time someone knows I was in the Army and that I want to be a pharmacist, and the interviews were no exception.
After all, it does seem rather disjointed. Going from essentially humanities degrees to the military to a degree in pharmacy and a wholly different job than my record seems to suggest I'd do was a challenge to explain. Then again, it was pretty easy at the same time, because I was honest.
I got out of the Army not wanting to really work in direct government service again (i.e., as a contractor or DA civilian) so that eliminated pretty much every security / analyst position they offered me after I was discharged. Next, I didn't really want to finish a graduate degree in Biopsychology or MCB, and I had the perfect storm of taking classes in California Drug and Alcohol Abuse counseling and my aunt, who is a cardiologist, suggesting I look into health field careers. She didn't initially suggest pharmacy but her suggestions, such as CLS and Respiratory Therapy got me into the mindset, then the brief intro. on pharmacokinetics made me fall in love and, as my name suggests, I discovered what I've deemed a "late onset" love of science!
And that was obviously good enough for the folks at UoP. Honesty IS always the best policy. These people are professional interviewers for the most part. They see hundreds of people every year and they can smell BS a mile away.