The land bridge over the bering strait joined modern day a) greenland and canada b) alaska and siberia c)greenland and siberia d)alaska and canada

B) Alaska and Siberia  

Explanation:

A portion of the Bering Sea water goes through the strait into the Arctic Ocean, however a large portion of it comes back to the Pacific. In winter the locale is liable to serious tempests and the ocean is secured by ice fields averaging 4 to 5 feet thick.

In midsummer, float ice stays in the Bering Strait. The strait is named after Vitus Bering, a Danish commander, who cruised into the strait in 1728. During the Ice Age, the ocean level fell by a few hundred feet, making the strait into a land connect among Asia and North America, over which a significant movement of plants and creatures, just as people (around 20,000 to 35,000 years ago), happened.

answer: karl marx, max weber, and emile durkheim (the fourth could be considered georg simmel)

explanation:

the exclusive possession or control of the supply or trade in a commodity or service.