Maesanin, the active ingredient in an herbal tea used by East Africans to ward off cholera, (has an antibacterial action but by a mechanism that is neither understood nor simmilar to that of )other antibiotics.

a. has an antibacterial action but by a mechanism that is neither understood nor simmilar to that of
b. has an antibacterial action by a mechanism that is not understood,however,nor simmilar to
c. has an antibacterial action, but it does so by a mechanism that is neither understood nor simmilar to that of
d. acts against bacteria by a mechanism that is not understood,however, and is different from
e. acts against bacteria,but it does so by a mechanism that is not understood and is different from that of

oa E