Question

The shells of clams and oysters collect on the seafloor. Over time, they form a rock. What type of rock is it?

Answer 1

Sedimentary.

Explanation:

There are three kinds of rock:

Igneous, from the Latin word for "fire" -- rocks formed from volcanic action. Includes "slow" versions of volcanoes like the magma/lava welling up beneath the Atlantic Ocean.

Sedimentary -- Sediments refer to deposits like sand, shell, or soil. Over time accumulated sediments get compressed by additional deposits and become rock.

Metamorphic, from the Greek word for "to transform" -- refers to rocks formed from gradual transformation of other rocks.