Is there such thing called a catchy and fast rhythm or is it a catchy and fast beat

In music the beat always determines what kind of s song it will be. like songs with a backbeat tend to be rock or hip hop or something and end up more popular while songs without one tend to be more like classical. so yes it's the beat

Both actually. There is a thing called a catchy and a fast rhythm and a fast beat.

The correct answer is c.