One Reason That Malaria Continues to Be the World's Most

One reason that malaria continues to be the world's most significant infectious disease is because Plasmodium falciparum continues to develop resistance to the drugs that have been used to treat malaria.This is due to which of the following?

A) Some Plasmodium falciparum have pre-existing mutations that make them resistant to antimalarial drugs
B) Some mosquitoes have pre-existing mutations that make them resistant to antimalarial drugs
C) Some people have pre-existing mutations that make them resistant to antimalarial drugs
D) The antimalarial drugs cause mutations to occur in Plasmodium falciparum
E) The antimalarial drugs cause mutations to occur in the mosquito