Answer:
size of that species’ population.
Step-by-step explanation:
The increase in the reproductive success of a species will have the greatest impact on the size of that species’ population.
A reproductive success rate means more individuals survive birth and get added to the existing population. The more the number of individuals added to a population, the more the size of the population of the species.
An increase in the population size of a species will only increase intra-species competition for resources but have no real impact on the success of other populations in the community.