The Chemical Composition of Seawater

The chemical composition of seawater

A) contains 18 elements which account for 75% of the dissolved solids in seawater.
B) contains dissolved gases,suspended and dissolved organic matter,and many trace elements.
C) is exceptionally heterogeneous,varying across the vast oceans of the world.
D) has varied greatly over the Earth's history.
E) is highest in salinity near large landmasses and at higher latitudes.