Which statement about the composition of ocean water is true? A. When surface water becomes more dense than the water below, the surface water sinks, which is called an ENSO. B. When surface water becomes more dense than the water below, the surface water sinks, which is called upwelling.
C. A water column with greater density differences between the layers is more stable than one with smaller density differences between the layers.
D. A water column with smaller density differences between the layers is more stable than one with greater density differences between the layers.

the element that provides strength to the exoskeletons of clams and oysters is phosphorus. this is so because calcium carbonate is the main component in the shells.

explanation:

it is either c or d and i know for sure it is not a or b

the correct answer is - d. china has a large and growing population.

the fact that china has a large (the biggest) population, and it is still growing, doesn't hinder the agriculture production in the country. in fact, it can for increased production in the agriculture, since there's more labor force, as well the sheer mass of people produces lots of scientists that come up with new inventions as to how to improve this sector. nice example is the inner mongolia region in china, in general dominated by the gobi desert, but few scientist came up with a nice idea as to how to make the region productive by using plants that are very resistant to droughts, so lots of people have been employed, and the region is becoming greener and greener each year, and the production of food in this region is also increasing.