B
Below is a question with multiple-choice answers. Choose the correct option based on your reasoning.

### Question:
Astronomers and biologists study different areas of science. Many astronomers observe far distant objects in the sky. Many biologists study extremely small objects. What do these astronomers and biologists have most in common?

### Choices:
A. They both examine the history of life on Earth.
B. They both make discoveries using optical devices.
C. They both study how organisms change over time.
D. They both search for evidence about the origins of the universe.

### Answer:
