Final answer:
Odorants must indeed be volatile to be detectable by the receptors in our olfactory system. These volatile chemicals can become airborne and stimulate the olfactory neurons in the nose, confirming that the statement is true.
Step-by-step explanation:
The question 'Odorants must be volatile to be smelled, true or false?' touches upon the subject of biology, specifically the olfactory system. Odorants, which are volatile chemicals, must be capable of entering the gas phase at ambient temperatures to be inhaled and detected by the olfactory receptors. These odorant molecules bind to receptor proteins in the olfactory neurons, which are located in the olfactory epithelium in the nasal cavity. Since volatile substances have low boiling points and weaker intermolecular interactions, they can easily evaporate and become airborne, allowing them to stimulate the sense of smell. Therefore, the statement is A) True.