Here's why:

* Carbon exists in different forms: The most common forms of carbon are graphite and diamond. Both of these are solid.

* Graphite: A soft, slippery solid used in pencils and lubricants.

* Diamond: The hardest naturally occurring substance known, prized for its beauty and durability.

However, carbon can be found in other states under specific conditions:

* Gas: Carbon exists as a gas in the form of carbon dioxide (CO2) and carbon monoxide (CO).

* Liquid: Carbon can exist in a liquid state at very high temperatures and pressures.

So, while carbon is primarily a solid at room temperature, it can exist in other states depending on the circumstances.