Some germs rely on insect carriers – such as mosquitoes, fleas, lice or ticks – to move from host to host. These carriers are known as
vectors
virus
bacterium
O meningitis

vectors

I hope i'm correct but according to the given choices none of it is correct besides vectors.

d. everyone should be treated fairly.

delegated (sometimes called enumerated or expressed) powers are specifically granted to the federal government in article i, section 8 of the constitution. this includes the power to coin money, to regulate commerce, to declare war, to raise and maintain armed forces, and to establish a post office.