Ocean currents have an effect on the earth's climate. What evidence from the passage supports this conclusion?
A Some ocean currents, like the Gulf Stream, have a direct effect on the
climates of the countries they pass.
B The gradual increase of the earth's temperature has been a topic of much
debate.
С Cold water does not always stay at the bottom of the ocean.
D As water freezes in the North and South Poles, the water surrounding the
ice becomes saltier and colder.