Sometimes you just need to put them in their place. He was an O-4.
I'm pretty blunt with people and that extends to bosses. When someone makes a request like that of me at work, my default is to either completely ignore said request (whether it was communicated written or verbally) or to reply with some snark along the lines of,
"My ass is too pale and my legs are too hairy to be a secretary"
EDIT: I understand snark doesn't always have a place within the service.