My vote is for D.
I might be wrong, but I am not sure if "as well" can be used here. Can somebody explain with an example when one needs to you as well.
C is ruled out because the usage of 'but' provides an exception. If we use 'but' there should have been something that should help the economy.
Over B and D, I chose D as it is more concise and sounds good (atleast to me
Waiting for a better explanation and the OA.
510 on my first GMAT. 610 on second GMAT.!
The struggle continues.