This question is driving me nuts. I know it's supposed to be an easy question but I don't understand how (D) is correct.
To summarize:
The stimulus tells us that most regular coffee is made from arabica beans because because it has a richer flavor than coffee made from robusta beans that people prefer. BUT people who drink decaffeinated coffee prefer robusta bean coffee because the flavor isn't affected as much by decaffeination as arabica bean coffee is. Then we're told decaffeination reduces/removes some things, most of which are flavor-neutral, but one that contributes to the richness of the coffee's flavor.
Ok. We know that somehow during the course of decaffeination the richness of robusta bean coffee decreases less than arabica bean coffee. But how do we know this is because of the amount of a substance, as D suggests? It might be because these substances interact with other substances in the beans in different ways, or maybe there are multiple substances that have to removed from arabica beans that don't have to be removed from robusta beans.
Anyway, I just don't see the connection between the decaffeination process and the amount thing in (D). Can someone enlighten me? Thanks!!