What causes the sinking of water in the northern atlantic ocean, which to drive the ocean conveyor belt?

a) the low salinity water coming from the south gains salt and becomes more dense.

b) the high salinity water coming from the south warms and becomes less dense.

c) the high salinity water coming from the south cools and becomes more dense.

d) the low salinity water coming from the south looses salt and becomes less dense.

The high salinity water coming from the south cools and becomes denser.

Explanation:

In North Atlantic Ocean north, Atlantic deep water is formed. Flow of warm water surface from southern water surface into the Atlantic Ocean Thermohaline circulation is involved. Regulation of global system of current is called global conveyor belt.

In north Atlantic nearest pole conveyor belt begins which is in the surface part of the ocean. Due to temperature of Arctic water become chilled. When ice become freeze and salt can’t be freeze then it left in ocean than the water become salt.    

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.

the fossil record provides evidence of a common ancestor to many species.