Answer: A community
Explanation: Abiotic is not living, all the things mentioned are alive so this is not correct.
A population is a number of organisms of the same species living together in an area at the same time.
A community is an interacting group of various species in a common location. The common location here is a pond.
A food chain shows the flow of energy and material being transferred from one organism to the next. The example given could be a food chain, but what disqualifies it from being a food chain is the perch it does not provide energy to any of the organisms listed in your example.