The biggest challenge that Costa Rica will likely face in its dedication to conservation and restoration in the future is

A) the pressures of its growing population.
B) its small size (as a country), which may not be able to maintain large enough reserves.
C) the potential for disturbance of sensitive species in reserves by ecotourists.
D) spread of disease and parasites via corridors from neighboring countries.
E) the large number of Costa Rican species already in the extinction vortex.