Apopulation of 100 butterflies living on an acre of land loses three-quarters of its members when a sudden freeze in the spring occurs just after they emerge as caterpillars. this population has undergone a reduction in population size due to

a. a density-independent factor.
b. natural selection.
c. an intrinsic factor.
d. a density-dependent factor.

Option A (Density-independent factor)

Explanation:

Density-independent factor is a population regulation factor that affect or influence the size of a population without considering the population density. Climate and weather are the main density-independent factors in nature.

Their effects increment is directly proportional to the increase in population size. These factors are environmental agents that checkmate the size of a population without putting the reproductive and behavioral patterns of the organisms into consideration.

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.