When does a population experience logistic growth?

a. when it has access to unlimited resources
b. when it reaches the carrying capacity
c. when natural predators are introduced to the population
d. when there's primary succession

When the population attains the condition called carrying capacity, it causes logistic growth in the population.

Option B

Explanation:

The rate of development of population in an environment depends based upon the number of individuals surviving in the environment. It develops in size gradually when there are just a couple of people whereas it develops quicker when there are more people.  

When the population reaches the carrying capacity of the environment which is nothing but the maximum number of individual which the environment can hold, it causes logistic growth due to non availability of resource as it is exhausted by the surviving population.

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