Adrug that has been reported to produce an increase in sociability and euphoria, as well as an increase in blood pressure, body temperature, and pulse is

Answer - 3,4- (MDMA)

MDMA is popularly known as Ecstasy. Currently, it has no accepted medical uses but is used as a recreational drug. Reportedly, its psychoactive effects include an increase in sociability and euphoria; while physiologically, it increases blood pressure, body temperature, and pulse.

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."