Which condition causes ocean salinity to increase?

A.

river water flowing out into the ocean

B.

high levels of precipitation

C.

high levels of evaporation

D.

thawing of polar ice caps

At the simplest level, salinity is the total amount of dissolved material in grams in one kilogram of sea water. Thus salinity is a dimensionless quantity. It has no units. The variability of dissolved salt is very small, and we must be very careful to define salinity in ways that are accurate and practical. so it would be (D)