Two similar species of fish live in the same lake. a biologist observes that one fish population is much larger than the other. the biologist believes that the difference is due to better protective coloration in the larger population. a research project is set up to test this idea. the biologist's idea that the population numbers are influenced by coloration is called a(n) a. opinion. b. hypothesis. c. conclusion. d. observation.

D. observation.

Explanation:

Observation can be define as a process of monitoring or visualizing the natural phenomena, an experimental procedure, or changes in the body of the living or non-living sample under study. This process helps in obtaining a conclusion and result of the research question or experimental study.

The coloration is a observable parameter which can be used to frame the conclusion and result of the given study. Hence, the biologist idea will be influenced by observation.      

condensation. good luck!