Which substance would most likely form sedimentary rock? cooled lava melted rock changed igneous rock small pebbles

The substance would most likely form sedimentary rock - small pebbles

Sedimentary rocksare formed by the accumulation of sedimentsSedimentation is the collective name for processes that cause these particles to settle in place.Pieces of rock are loosened by weathering, then transported to some basin or depression where sediment is trapped.If the sediment is buried deeply, it becomes compacted and cemented, forming sedimentary rock.small Pebbles can be called a rock when they are cemented and create a conglomerate – a clastic sedimentary rock.

Thus, The substance would most likely form sedimentary rock - small pebbles

Learn more:

link

The answer is observations and interpreting.