I always try to be the bigger person & will kill em with kindness, given the opportunity.

Shake his hand, and tell him I didn’t wash my hands after using the restroom

I would just walk by if l was really pissed. I have a habit of totally tuning out some people. They do not exist in my world. I'm not saying it is a good habit, but it is what l do.

I would shake his hand but with a look that let them know that I was a bigger person by doing so and don't even say or a word or I might just forget that and let loose..in other words, shake my hand, shut up, and move on.

tRump at Bush's funeral. No, I do not shake his hand. But I wish Michelle would have squeezed and brought him to his knees. Would have made my week.

I would greet them and shake their hand. My manners do not require liking or respecting somebody.

Skip to next person and ignore the asshat.

Depends on the insult. Was it deliberate, and out of spite or because of something else. I might just look them in the eye, stoic, and not shake their hands. Letting them know that I "recognize" them, but do not "acknowledge" them.

I would shake his hand and move on. I am reminded of the expression, "sticks and stones may break my bones, but words will never hurt me".

Ignore.
I am terrible at pretending to like people.

I would shake his hand and forget about the issue unless it was about my family ,myself or one of my employees. I might just crush his hand in a handshake.