The Insecticide DDT Kills Mosquitoes and Does Help Control Malaria

The insecticide DDT kills mosquitoes and does help control malaria when it is first used. Why don't we use it?

A) It's extremely toxic to other organisms (including humans) , and the mosquitoes quickly become resistant.
B) It's extremely expensive so the developing countries that could best use it can't afford it, and the mosquitoes quickly become resistant.
C) Malaria isn't enough of a problem that we should risk using something so toxic.
D) Screen doors and medical care work better in the short term.
E) Instead we use it to control insects on crops, and there isn't enough to go around.