Answer:
A. resource partitioning.
Step-by-step explanation:
Resource partitioning refers to as the division of limited food or resources by organisms in order to prevent competition in an environment. In situations where there are limited resources or food available to organism s in an ecological niche, such organism in that niche will need too develop strategic ways to coexist and to prevent competition, so that the resources can be shared across.
The birds illustrated in the question above are therefore experiencing resource partitioning.