再求教 OG 149

保家为国

149. Last year, land values in most parts of the pinelands rose almost so fast, and in some parts even faster than what they did outside the pinelands.
(A) so fast, and in some parts even faster than what they did
(B) so fast, and in some parts even faster than, those
(C) as fast, and in some parts even faster than, those
(D) as fast as, and in some parts even faster than, those
(E) as fast as, and in some parts even faster than what they did

为什么than,those之间加逗号，E为什么不对？they did不是和rose对应的吗？Key D

有劳各位了！