SafeZone mosquito repellant has been shown in laboratory settings to be effective for twelve hours against the female anopheles mosquito, the only mosquito that transmits malaria. SafeZone, however, is not effective against mosquitoes that do not transmit malaria. The only instance in which SafeZone does not repel the female anopheles mosquito is if the mosquito can detect any blood, however small the amount, on a person’s body. Therefore, assuming one does not have any blood on their skin before applying SafeZone, one will not be able to catch malaria for up to twelve hours.

Which of the following, if true, would argue most against the use of SafeZone in areas in which malaria is endemic?

A) SafeZone mosquito repellant has been shown to cause irritation that may result in a mild rash.
SafeZone -> Mild rash -> additional assumption "mild rash" cause blood -> Female mosquito attracted = SAFEZONE doesn't work
BUT we bring outside assumption, we are unsure that mild rash -> Blood = might weaken or not 50% accuracy

B) The culex mosquito, a different species of mosquito, is found in many areas where the anopheles mosquito is found.
OOS, no link between Culex Mosquito and Malaria.No impact of prevention of malaria by SafeZone

C) The male Anopheles mosquito also feeds on human blood and is active at the same time as the female.
Male Anopheles -> Bite human -> blood ( 100% sure, you can try) -> Female anopheles -> Malaria - SAFEZONE doesn't work 100% accuracy

D) Once a person has contracted malaria, he or she may experience both bleeding gums and a bloody nose.
OOS, person already having malaria no link with prevention of malaria and Safezone

E) Some mosquitoes, after biting a person covered in SafeZone, can go on to bite a person not covered in SafeZone.
Only Male Anophele attacks people with SafeZone -> Male Anophele = No Malaria -> If Male bite some else after with Safezone no risk to get Malaria as only female bring Malaria. No impact of prevention of malaria by SafeZone

C is the answer. This question requires test takers to read carefully each specifically word like RC questions.

First, " ruptured blood vessels" are caused by bites from any kind of mosquito -> leading to the failure of SafeZone
C tells that male mosquito is active -> leading to more "ruptured blood vessels"