One limitation of food webs in representing an ecosystem is that they do not A. Include producers in the ecosystem
B. Show consumer in the ecosystem
C. include all species in the ecosystem
D. Show predator prey relationships

I think D (This isn't verified as correct, only my best concluded answer in terms of correction.)

Explanation:

The reason why I believe D is the answer is because the other answers are included in a food web. The reason for considering D is because I'm pretty sure that consumers are apart of a food web which could be logical for eliminating answer B. D would be a good answer considering that a food web consists of producerd and consumers and the transfer of energy. Relative to whether that's considered as a predator prey relationship other than an energy transfer relationship then D would probably be your answer.