Despite the Loss of the Atlantic Forest Habitat of Brazil

Despite the loss of the Atlantic forest habitat of Brazil, no extinctions of birds from this area have been reported. According to Brooks et al., which of the following is the most plausible explanation for the apparent lack of extinctions?

A) Birds have gone extinct, but biologists have not observed the extinctions.
B) Birds are adapting to inhabiting forest fragments.
C) Birds are adapting to inhabiting deforested areas.
D) The time lag between deforestation and extinction has not played itself out.