So, I already searched this site and found my original question (that is, the question I wanted to ask), which is, can we favorite an answer? The answer is no, you can favorite a question.
So, I am here with a feature request of favoriting an answer.
If I favorite a question, it does keep track of the question in my favorites, but it gives credit to the question asker. However, I often find nice answers, e.g. this one, to questions that aren't that exciting and I favorite the question to keep track of that nice answer. There are even badges that depend on how often a question is favorited. We could easily have similar badges for answers that are favorited and then people can actually give credit where they want. I don't have to upvote a question because I like an answer to it. I upvote the answer itself.
Or, imagine a question with many answers and I really like 3 of them. I would like to catalog these various wonderful answers as my favorites, not just favorite the question once. When I look at a favorite question later, I can't really tell why I favorited it. I might have to scroll through the question and all answers to figure out why I favorited it. And, then, I might only see 1 of the nice answers (without spending a lot of time looking through all answers) and assume that's why I favorited it.