Ineed .

which of the following explains the primary difference between deep currents and surface currents?

a. surface currents move much more slowly, while deep currents travel quite
quickly.
b. deep currents are driven by density differences, while surface currents are
driven by wind and earth's rotation.
c. deep currents transport ocean water from north to south, while surface
currents transport water from east to west.
d. surface currents don't have much impact on earth's climate, while deep
currents do have a large impact on the climate.