Here's a problem to solve: Which comparison of butterflies and moths is a statement of fact?

Among the 4 following options, which is the correct answer?

- A: Butterflies are prettier and more fun to watch than moths.
 
- B: Butterflies are better at flying than moths.
 
- C: Butterflies and moths are much happier during the daytime.
 
- D: Butterflies and moths have equal numbers of legs.
 