No bashing, I have even taught for a short while and the only dumb questions students asked is when they were trying to be an ass. In our case here we do not know the answer so even wild ass guesses are legitimate until we weed them out. (ha ha) I don’t care who or where the answer comes from, I just want the answer. But on a brief look, I can not find what is taken as the answer to it in weed circles, that it is chlorophyll.
Just do it. Google “green plant smell”. Then “green plant smell hay”. It is good for a laugh.