Boost the tourist trade always favors aviation. You have to get to a foreign country somehow. D is not the answer.
Creating wealth is not a hindrance to any industry. So A is incorrect.
B is kind of tough to get rid of. If aviation is already there you don't want to compete with an established industry. It is wrong only because C is a better choice.
Answer. C.
<span>2^(3x)/2^y = 2^(3x-y) = 2^12 = 4096</span>