Except for drones less than 7.5 ounces (approximately) I'm all for a knowledge test for drone operators. This is similar to what ham radio operators have to do. Passing the knowledge test would be prerequisite for drone operator license, which you should need in order to purchase or fly a drone. I was sure I heard that drones over 7.5 ounces (approximately) now had to be serial numbered and registered, which should mean that the Feds should be able to nail any misbehaving drone operators.

https://www.faa.gov/news/updates/?newsId=85264