Which of the following olfactory substances does not belong to terpenes? ( ) A: α-terpinene B: 2-trans-hexenal C: Thymol, longifolene D: Pigeritone

Thyme, ____,<br/>yields a medicinal oil containing thymol. A: a fragrant garden herb B: garden herb which is fragrant C: fragrant garden herb D: is an herb in a fragrant garden