Why Is the Surface Salinity in the Tropics So Much

Multiple Choice

Why is the surface salinity in the tropics so much higher than that of the equator or high latitudes?

A) There is a higher evaporation rate in the tropics.
B) There is a higher rate of precipitation in the tropics.
C) There are more continents in the tropics,and thus more sediment weathered.
D) There is a large influx of freshwater from rivers along the equator.