Although the lesser cornstalk borer

[BTGmoderatorDC]

Although the lesser cornstalk borer is widely distributed, control of them is necessary only in the South.

(A) the lesser cornstalk borer is widely distributed, control of them is
(B) widely distributed, measures to control the lesser cornstalk borer are
(C) widely distributed, lesser cornstalk borer control is
(D) the lesser cornstalk borer is widely distributed, measures to control it are
(E) it is widely distributed, control of the lesser cornstalk borer is

What is wrong with the other Options? Can some experts help me?

OA D

[VJesus12]

I think options B and C are to different from the other 3 ones. But, I don't know how should I discard them.