I'd say C because you can't scientifically decide if a person is a good person or not
A isn't right because you can guess what's in the box by weight or sound
B isn't right because you can physically open a clock up or something to see how it works
D isn't right because you can gather data based on what food the dog takes a liking to
E isn't right because you can gather data of the nutrition of popcorn and apples
So that leaves C
<span>visible light radio waves and gamma rays</span>