Final answer:
When two trees of the same species compete for resources such as sunlight and soil nutrients, this is known as (B) intraspecific competition. This differs from interspecific competition, which occurs between different species.
Step-by-step explanation:
Two trees of the same species that grow very close together and vie for sunlight and soil nutrients are an example of intraspecific competition. This type of competition occurs between members of the same species as they strive for the same limited resources, such as light, water, and nutrients. One common outcome of intraspecific competition is that some individuals will outperform others. In the given example, one tree may grow taller to access more light, thereby becoming better adapted to its environment and outcompeting the other tree for survival.
In contrast, interspecific competition happens when members of different species compete for resources. For instance, if two different species of trees, each requiring similar nutrients or sunlight, grew in the same area, they would be engaged in interspecific competition. The species that are better suited to the conditions of the environment typically have a competitive advantage.