The complete combustion of a gaseous hydrocarbon in excess oxygen releases thermal energy according to the general balanced equation below:

\[ \text{C}_x\text{H}_y\text{(g)} + \left(x + \dfrac{y}{4}\right)\text{O}_2\text{(g)} \rightarrow x\,\text{CO}_2\text{(g)} + \dfrac{y}{2}\,\text{H}_2\text{O(g)} \quad \Delta H^\circ_{\text{comb}} < 0 \]

Let \(q_{\text{O}_2}\) represent the magnitude of the energy released per mole of \(\text{O}_2\text{(g)}\) consumed, and let \(q_{\text{H}_2\text{O}}\) represent the magnitude of the energy released per mole of \(\text{H}_2\text{O(g)}\) produced during the reaction. If an experiment determines that the ratio \(\dfrac{q_{\text{O}_2}}{q_{\text{H}_2\text{O}}} = \dfrac{2}{3}\), which of the following could be the identity of the hydrocarbon?