Which of the following is compressible?

Gases have larger molecular space between their molecules therefore they are highly compressible. But in the case of solids, there is less or no intermolecular space between the molecules therefore solids cannot be compressed.

Out of the solid only carbon dioxide is a gas and therefore it is compressible. It can be liquified by applying pressure at room temperature.

Steel, wood and glass are solids and cannot be compressed.