Question

which trophic level has the least biomass?
a. 1
b. 2
c. 3
d. 4
e. 5

Explanation:

Step1: Recall biomass - trophic level relationship

In a typical ecosystem, biomass generally decreases as we move up the trophic levels. Producers (like phytoplankton) have the most biomass as they form the base of the food - web. Higher trophic levels have less biomass.

Step2: Identify the highest trophic level among options

Crustaceans (level 4) are higher in the trophic levels compared to phytoplankton (level 5 which are producers). Higher trophic levels have less biomass. Among the options given, the highest trophic level is 4.

Answer:

D. 4