Okay, not THE most offensive thing, but my mom will have all these misconceptions about EVERYTHING she doesn't understand. What bothers me is that she doesn't know what she's talking about, but still insists she's a freaking expert. Then she will either crack jokes based on her ideas, or get offended at her image of things. For instance, she thinks she knows all about male and female sexuality, and won't admit she doesn't. She thinks any deviation from heterosexuality is situational or the effect of events. The former being men, the latter being women. She also thinks transfolk are just imitating offensive caricatures of the opposite biological sex. I could go on.
