Answer
b.
Work Step by Step
Option a. is incorrect. The pH level of the pond water rises and falls throughout the day.
Option c. is incorrect. The pH level of the pond does not waiver too much so that no organisms can survive. Organisms of some kind can survive in different pH levels.
Option d. is incorrect. In fact, the pH level of the pond is lower (more acidic) at night than during the day.
Option b. is correct. During the day, pH levels are the highest (most basic) whereas at night, the pH levels of the pond are the lowest (most acidic).
