#### Answer

c.

#### Work Step by Step

Option a. is incorrect. The carrying capacity is the maximum number of organisms of a species of a particular area can support with its resources.
Option b. is incorrect. Logistic growth refers to the growth of a population according to a certain pattern of exponential growth, slowing, and finally cessation of the growth.
Option d. is incorrect. The population growth rate is how a population's numbers change.
Option c. is correct. The population density measures how many individuals of a species live in a specific unit area.