* Coal is formed from the accumulation and compression of plant matter over millions of years. The decay and transformation of this organic matter create the distinctive black, carbon-rich rock we know as coal.

Let's look at the other options:

* Limestone is primarily formed from the accumulation of marine organism shells, particularly calcium carbonate.

* Sandstone is formed from the accumulation and cementation of sand grains.

* Shale is formed from the accumulation and compaction of clay and silt particles.

While limestone, sandstone, and shale are all sedimentary rocks, they are not formed from decayed organic matter like coal.