The toxin of Vibrio cholerae causes profuse diarrhea because it
A) modifies a G protein involved in regulating salt and water secretion.
B) decreases the cytosolic concentration of calcium ions, making the cells hypotonic.
C) binds with adenylyl cyclase and triggers the formation of cAMP.
D) signals IP3 to act as a second messenger for the release of calcium.
E) modifies calmodulin and activates a cascade of protein kinases.
