Answer:
C. Scientific theories explain why something happens, and scientific laws describe what happens.
Step-by-step explanation:
Scientific Theory: Explanation of something in the natural world that can be tested over and over again via scientific method and it is supported by evidence. e.g. Darwin's Theory of Evolution
Scientific Law: Description of an observation of something that occurs in the world.
Basically Scientific Theory is the How and Why but Scientific Laws are the What
Hope this helps!