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

### Question:
A student uses a pH meter to measure the acidity of a water sample from a lake. For what purpose is the student most likely testing the water?

### Choices:
A. to learn what organisms could survive in the lake
B. to determine the age of the lake
C. to understand how people use the lake
D. to find out the depth of the lake

### Answer:
