The sociologist who conducted extensive research on varying rates of suicide within a specific country and among different countries was

Emile Durkheim

Explanation:

Émile Durkheim developed the first sociological study on the matter, where he examined rates in his community as well as in other countries.

He concluded that individual temperament was not enough to explain such a painfull act, and there seem to be social causes behind it. While societies that were more socially integrated and connected had a lower tendency to do it, lower social integration makes it more likely to happen.

its kind of blury sorry

d.) continue to rise rapidly