What are the best adjectives to describe someone who always answers back and always has something to say?
If you can allow for colloquialism in you report use a word that is maybe less official but descriptive like wise-cracker. I am not sure if it is a legal word to describe a person; it sure can be use as adjective as in wise-cracking. You can go farther down and say wise *** or smart ***, which probably will be the best description, alas a controversial one. You can say wise guy, a less formal depiction which doesn’t require using foul language, although it also is used in informal language. If you want something more formal and also to the point I would go with pertinent or if you need a noun: meddler, or intruder.