Question

mud was deposited at the bottom of a deep ocean. over time, the sea level began to drop, and the area became a shallow part of the ocean. a coral reef formed on top of the older sediment. sediment made mostly of the shells of marine organisms was deposited.

as the sea level continued to fall, the area became part of a beach, and sand was deposited.

when the sea level fell even further, the area became part of a valley. sand and pebbles were deposited by a fast - flowing river.

a rock sequence formed from the sediment layers described above. put the following rocks in order to show what this rock sequence probably looked like.

younger
limestone
shale
sandstone
conglomerate

Explanation:

Step1: Match rocks to sediments

Mud → shale; shell sediment → limestone; beach sand → sandstone; river sand/pebbles → conglomerate.

Step2: Order by deposition time

Oldest first: deep ocean mud (shale) → shallow ocean shells (limestone) → beach sand (sandstone) → river sand/pebbles (conglomerate). Youngest at top.

Answer:

younger
conglomerate
sandstone
limestone
shale