C. It transports heat from the North Atlantic to the Indian Ocean.
Explanation:
The Antarctic Circumpolar Current is a massive oceanic current that circles around the Antarctic continent, that plays many roles.
One of the roles it plays is to connect all three major oceans (Atlantic, Pacific and Indian) together, and acts as a transportation system between them transferring heat, salt and other elements.
That role is vital in the global ocean thermo-regulation system of the planet.
