What physical state might a substance with a simple molecular structure exhibit at room temperature?

A substance with a simple molecular structure can exhibit either a gas or a liquid state at room temperature due to the relatively weak intermolecular forces that hold the molecules together. These forces, often van der Waals forces or dipole-dipole interactions, are not strong enough to keep the molecules in a solid state under typical conditions, allowing them to either be in a gaseous state or a liquid state.

Many simple molecular compounds, such as water (which is a liquid at room temperature) and carbon dioxide (which is a gas at room temperature), demonstrate this behavior. Thus, the variability in the physical state is characteristic of substances with simple molecular structures, making it plausible for them to be found in either the liquid or gaseous state.

Other options provided suggest more restrictive physical states which do not account for the diversity observed among simple molecular compounds.