Idris has decided that his research project is going to be a descriptive investigation of an intertidal pool. The data he collects will MOST likely be which of the following?

A. the names of organisms in the intertidal pool
B. the number of organisms in the intertidal pool
C. the size of organisms in the intertidal pool
D. the temperature of organisms in the intertidal pool

B. the number of organisms in the intertidal pool

This is because a descriptive investigation typically focuses on gathering information about the characteristics of a particular phenomenon or subject, in this case, the intertidal pool. Counting the number of organisms in the pool would be a relevant and important aspect to include in a descriptive study of the intertidal pool.