Most Natural Food Chains Are Only Four or Five Links

Multiple Choice

Most natural food chains are only four or five links long. The number of trophic levels is limited because

A) there are more predators than herbivores.
B) the efficiency in the conversion of food eaten at each level is very low, about 10 percent.
C) winter kills off most insects and stops the food chains.
D) space in the ecosystem is limited and so very few larger organisms can live there.
E) nutrients stop cycling after the fourth or fifth trophic level.