At the annual stockholders meeting, investors heard a presentation on the numerous challenges facing the company, including among them the threat from a rival's multibillion-dollar patent-infringement suit and the declining sales for the company's powerful microprocessor chip.

A. including among them the threat from a rival's multibillion-dollar patent-infringement suit and the declining sales for
B. which includes the threat of a rival's multibillion-dollar patent-infringement suit and declining sales of
C. included among these the threat from a rival's multibillion-dollar patent-infringement suit as well as a decline in sales for
D. among them the threat of a rival's multibillion-dollar patent-infringement suit and the decline in sales of
E. among these the threat from a rival's multibillion-dollar patent-infringement suit as well as the decline in sales for

OA: D

can someone explain why B is wrong?

[spoiler]A)[/spoiler]the parallelism doesn't make sense (threat and declining sales
[spoiler]C)[/spoiler]"threat from" is used for people.
[spoiler]E)[/spoiler]among THEM is better than THESE

is there more things i should be knowing?
plz correct me if i'm wrong.

thank u!!