Thought by some to prey on unsuspecting and vulnerable individuals, the government is still researching the structure of sub-prime mortgages in order to determine the best way to address some of the problems that they have caused.

(A) the government is still researching the structure of sub-prime mortgages
(B) the structure of sub-prime mortgage industry is being researched by the government
(C) the government are still researching the subprime mortgage industry's structure
(D) sub-prime mortgages, and the structure of that industry, are being researched by the government
(E) the government is still researching the structure of the sub-prime mortgage industry

OA D

Source: Princeton Review