The susquehanna river, which runs through the states of new york, pennsylvania, and maryland, received the designation "america’s most endangered river" in 2005. one of the river’s problems results from the large number of sewage overflow sites that are found along the course of the river. these sewage overflow sites are a direct result of an increase in
a. global warming
b. recyling programs
c. human population
d. atmospheric changes

The correct answer is option c. "human population".

Explanation:

A lot of studies suggest that an increase of human population in most cities results in an increase on the amount of sewage on nearby rivers. If a large number of sewage overflow sites are found in the Susquehanna River it is very likely that is a direct result of an increase in human population. More people living in the cities of the states of New York, Pennsylvania, and Maryland would directly result in an increase in the sewage overflow of the river.

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.