Question

the wind and rain brought into the river. over time, that material may form layers and harden into rock. fossil sediment magma

Explanation:

Wind and rain erode rocks and soil, creating sediment. Sediment is carried by water (like in a river) and over time, through processes like compaction and cementation, sediment layers can harden into sedimentary rock. A fossil is the preserved remains of a once - living organism and magma is molten rock beneath the Earth's surface. Neither fossil nor magma fit the context of material brought by wind and rain into a river that forms rock layers.

Answer:

sediment