African Sleeping Sickness Is Fatal If Not Treated Because the Parasite

Multiple Choice

African sleeping sickness is fatal if not treated because the parasite

A) evades destruction by the immune system by changing surface antigens.
B) produces a toxin which binds irreversibly to neurons.
C) is an intracellular parasite in RBC's, where they are not detected by the immune system.
D) reproduces so fast there is no time for an immune response to develop.
E) produces a non-immunogenic toxin the immune system cannot neutralize.