You see a sandy beach along a coastline. where did the sand come from

The sand is there due to weathering and decomposition of rocks and other minerals along the coastline, and there are constant waves of water near the coastline the slowly erodes the rocks near the coastline forming the granular particles we see when we visit beaches this action is perform by water waves over hundreds of thousands and millions of years

Your correct the answer is d

Magma forms by partial melting of upper mantle and crust. partial melt means that only a fraction of the available material forms a melt, and that the remainder stays solid. the partial melt rises because of its lower density and ascends through he crust. this is so conclusive mean the answer would be magma igneous rocks or balistic magma.