Question

where does competition for reproduction most likely occur?
ecosystem
community
organism
population

Explanation:

Reproductive competition happens between members of the same species, as they compete for mates, breeding sites, or resources to support reproduction. A population is defined as a group of the same species living in a specific area. An ecosystem includes all biotic and abiotic factors, a community includes multiple species, and an individual organism cannot compete with itself for reproduction.

Answer:

population