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

### Question:
Sandra puts some pill bugs into an open box. She covers half the box with a piece of cardboard. She then places the box outside on a summer day, and all the pill bugs move under the cardboard. The pill bugs are most likely responding to which of the following?

### Choices:
A. air pressure
B. bright light
C. wind
D. fog

### Answer:
