When a sedimentary rock melts and solidifies, it forms an igneous rock.

Here's why:

* Sedimentary rocks are formed from the accumulation and cementation of sediments like sand, clay, or organic matter.

* Igneous rocks are formed from the cooling and solidification of molten rock (magma or lava).

The process of melting a sedimentary rock changes its composition and structure, leading to the formation of a completely new rock type.