Green lacewings are used to control aphids, which are pests of many crops. A population of 1000 green lacewings is released into a farmer's field. The graph shows the change in the population over time.
What is the most likely explanation for the approximately constant population of the lacewings after the eighth year?
A. The lacewings had eaten all of the aphids in the field.
a
B. The lacewing population had reached the carrying capacity of the field.
C. New predators of lacewings had arrived in the field.
O
D. The birthrate of lacewings had increased, while the death rate remained constant.