I always answer the security questions with gibberish that I also save with my password manager. I now use a method like correct-horse-battery-staple to create answers, but I used to use long alphanumeric strings. I switched methods because, yes, one day I had to read the answer over the phone.
Rep: "Tell me the answer to this question."
Me: "Ok, let me see what I set it to..."
Answer: F^O9dA66@wUPpK5$lTXBbrQ#yLP1EGl$
Me: "Oh... Oh no."