Population growth that is unlimited by resource availability, which allows the population growth rate to increase continuously over time, is known as ______.

Correct option is B

Exponential growth refers to a population's rapid and continuous increase when there are unlimited resources and no environmental constraints. In this type of growth, the population size doubles over a fixed period, following a J-shaped curve. It is typically seen in bacteria, invasive species, and newly introduced populations in ideal conditions.
Explanation of each option:
· (a) Logistic growth – Incorrect. Logistic growth occurs when population growth slows down due to resource limitations and environmental resistance. It follows an S-shaped curve and eventually stabilizes at the carrying capacity of the ecosystem.
· (b) Exponential growth – Correct answer. In exponential growth, there is no resource limitation, so the population increases without restriction. It is observed in early-stage bacterial growth or when species are introduced into a new habitat.
· (c) Limiting factor – Incorrect. A limiting factor is any environmental condition (e.g., food, water, space, or predators) that controls population size. It prevents unlimited growth and shifts populations toward logistic growth.
· (d) Carrying capacity – Incorrect. Carrying capacity is the maximum population size an environment can sustain based on available resources. Once a population reaches this level, growth slows or stops due to competition and resource depletion.