I believe that the answer is A.
Answer:
d. Temperate regions have weak thermoclines (moderate in summer, less in winter)
Explanation:
The theromoclines and how strong they are are crucial for the movement and exchange of nutrients between the surface waters and the deeper waters. The nutrients are mostly found in the deeper and colder waters, so they only reach the surface and shallower waters when the thermoclines are weaker. With the movement of the nutrients toward the surface waters, they provide nutrition for the marine organisms, resulting in much larger populations and much more species to be present. The temperate regions are the ones where the theromoclines start to become weaker because the waters become cooler, especially in the winter when the temperatures are much lower and the waters become colder as well.
It’s would be B( the 2nd one).
The main mechanism through which the layering happened is gravity: it pulled the heavier, denser material to the center, leaving the less dense material on the surface.
The material that was on the outside cooled quicker, but this was the result, not the cause.
The answer is
<span>2) Gravity caused more-dense material to move toward the center of each planet.</span>