In an experiment freshly hatched larvae of an insect (Khapra beetle) were reared on a basal diet with increasing amounts of cholesterol. Results obtained are shown in the graph as above
Here, the graph shown is the sigmoidal curve, meaning the growth curve is following the normal pattern. Initially, there was the lag phase, where it adjusted to the environment of cholesterol and then it entered log phase, where Khapra beetle grew rapidly followed by the stationary phase. Thus, it means that cholesterol is essential dietary requirement for Khapra beetle. Hence, option A is the correct answer.