The right answer is D) weathering and erosion of rocks.
Sodium (Na) exists mainly in the oceans in the form of sodium chloride NaCl. This salt is derived from mines or saline rocks, by erosion of rock evaporite salt called rock salt or halite.
Calcium (Ca) exists mainly in the form of limestones, which are sedimentary rocks, just like sandstones or gypsums, easily soluble in water (see karst), composed mainly of calcium carbonate CaCO3, but also magnesium carbonate MgCO3.