In an experiment freshly hatched larvae of an insect (Khapra beetle) were reared on a basal diet (complete diet without cholesterol) with increasing amounts of cholesterol. Results obtained are shown in the given graph.

The graph indicates

• A

  cholesterol is an essential dietary requirement of khapra beetle

• B

  growth of khapra beetle is directly proportional to cholesterol concentration

• C

  cholesterol concentration of $2\,μg/g$ diet is the optimum level

• D

  growth of khapra beetle is inhibited when cholesterol concentration exceeds $5\,μg/g$ diet