What are two primary forces behind ocean currents. A:variation in water depth by latitude
B:density differences in water
C:the positions of earth, the sun, and the moon
D:energy transfer from winds

B:density differences in waterD:energy transfer from winds

Explanation:

The oceanic currents are produced by two major factors like the density difference and wind action.  They are fueled by the sun's solar radiation, Coriolis forces that is responsible for the rotation of the planet is also one of the major forces that make the current interact with the landforms. Difference produced due to high and low density of seawater that is due to the presence of salt contents.

Answer erosion,oil spills,pollution,tourism,urban development;

D. a mountain abd are made by volcanos and tectonic plates