The question is asking us to continue the sentence in: Biology and geology are two very different sciences, but biologists and geologists use scientific knowledge in the same way. These scientists both use scientific knowledge to... First, Geologists don't work with humans specifically, so we can reject answer D) Similarly, we reject answer B because it's only geologists who investigate Earth's different layers. Option C is again only true for one of the groups: the biologists! So the correct answer is A. answer questions and solve problems affecting the natural world.
