Here's why:
* Population: A population refers to a group of individuals of the same species living in the same area at the same time. In this case, the white-tailed deer within the forest constitute a population.
* Community: A community encompasses all the different populations of various species living together in an area. While the white-tailed deer are part of the forest community, the term "community" is broader.
* Ecosystem: An ecosystem includes all the living organisms (biotic factors) and the non-living components (abiotic factors) of a particular environment. The white-tailed deer are part of the forest ecosystem, but this term is even broader than "community".
Therefore, population is the most accurate and specific term to describe all the white-tailed deer in a particular forest.