Which of these is a vector of malaria fever?

The vector of malaria fever is the female Anopheles mosquito. Malaria is a disease caused by a parasite that is transmitted to humans through the bites of infected female Anopheles mosquitoes. When a mosquito feeds on the blood of an infected person, it ingests the malaria parasite which then reproduces within the mosquito. Later, when the same mosquito bites another person, it transmits the parasite to the new person through its saliva. Therefore, the correct answer to the question is "Female Anopheles mosquito" as it is the only mosquito species listed that is known to transmit malaria to humans. Male mosquitoes, on the other hand, feed on plant nectar and do not transmit the disease. The Culex mosquito is known to transmit other diseases such as West Nile virus, but not malaria.