Question

a. 10 kilocalories
b. 1 kilocalories
c. 100 kilocalories
d. 0.1 kilocalories

Explanation:

To solve this, we analyze the energy pyramid. Producers (plants) have more energy, and energy decreases by ~10% at each trophic level (10% rule). If producers have, say, 100 kcal, primary consumers (fish) get ~10 kcal (10% of 100). Among options, 10 kilocalories (A) fits the 10% energy transfer from producers to primary consumers.

Answer:

A. 10 kilocalories