As we know each time energy passes from trophic level to trophic level, a smaller amount of energy passes generally is applied the 10% rule, that is to say, that only te 10% of the energy in one level will pass to the second level, so if we apply this into the current problem we have that level 1 are producers, and the second level receives only 10% of the 25,000 available kilocalories, which is 25,000X0.10= 2,500, therefore the correct answer is the second option.