Malaria, a type of parasite, infects 500 million people each year by infecting the red
blood cells of its host. The virus, HIV, that causes AIDS, reports 50,000 newly infected
persons. Which statement best differentiates the pathogens, parasites and viruses?

There really isn't any information to differentiate... but from trying to understand your question, I'd say the first statement because it clarifies Malaria to be a type of parasite. Also, here is the difference between all three if you need to for future use:

Pathogens are disease-causing microorganisms. Pathogens are of different kinds such as viruses, bacteria, fungus, and parasites. Pathogens can be found anywhere including in the air, food and the surfaces that you come in contact with. While often confused as the same thing, bacteria and viruses are kinds of pathogens.

I hope this helps!

parasites can detrimentally affect their host, but also must not allow their host to die before they can complete their life cycle. some parasites have complex life cycles with many different hosts, and have had to find ways of persisting in many different environments during the change from one host to another. ectoparasites live outside the body of the host, and can more easily  disperse, but are  more exposed to predators, parasites, parasitoids. endoparasites live inside the body of the host, and are therefore protected from the outside environment. but they can be  attacked by the host's immune system. they have therefore developed  mechanisms for dispersal such as  complex life cycles.

multiplying and dividing the two decimals and the eqations by the same number of the overalls