Answer: A. Thermohaline circulation
Step-by-step explanation:
The thermohaline circulation is a phenomena which involves the movement of the oceanic currents because of the differences that occur in the temperature and salinity of oceanic water. These two factors changes the salinity and density of the water and fluctuating the climatic conditions. Cold water is particularly denser than the warm water. The water with more salinity is also denser over water with less salinity. The deep oceanic water currents brings changes in the density as well as the salinity of water hence, the circulation of water is called as thermohaline circulation. Some part of warm water will evaporate from the surface layer of the ocean this will lead to the flow of warm wind currents and water to the regions of cold regions of the seawater.
On the basis of the above description, A. Thermohaline circulation is the correct option.