Per capita expenditure = (Price x Volume)/ Population

So, for per capita expenditure to rise, any of 3 things have to happen
1) Price increases,
2) Volume increases,
3) Population decreases

Now, let's look at the choices

A) Will come back to this last.

B) Population increased. My formula tells me population can't increase. NOT B

C) High profit levels. Who gives a ****. NOT C

D) Generic drugs. Which means lower prices. My formula tells me prices need to increase. NOT D

E) No more marketing. Who gives a ****. NOT E.

A) That leaves us with A. Simple elimination. Now it could be possible that the new medications were more expensive. Higher prices. Satisfies my formula. Or the medications were not more expensive, but you don't know for sure. So, A is the "best" answer because all other choices are clearly wrong