There is no single answer.
It depends on your goals and your body. What are you trying to do?
Some powerlifting routines do 10 sets of a single exercise. DC training uses only one set per body part. You have extremes and everything in between.
It depends on the body part too.
I think biceps typically respond better to fewer sets...2-5 sets, but you have to tailer your reps and your intensity to this.
Speaking of which, your intensity, frequency, & volume must be put together in conjunction with each other to form the perfect program for YOU. The perfect program for me will undoubtedly be different than yours.