- A Total population size at the start of the observation period
- B Carrying capacity of the surrounding habitat
- C The intrinsic rate of natural increase
- D Time elapsed since the population began growing
Correct answer: C. The intrinsic rate of natural increase
Explanation: In the exponential growth model, r is the intrinsic rate of natural increase, reflecting the difference between birth and death rates under ideal conditions.
Concept context
How organisms interact with abiotic factors and respond to stress, plus population attributes, growth models, and interspecific interactions such as predation, competition, and mutualism.