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)....
(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
Baring in mind the error in "sales for" in option E, I still want to know whether the use of "among these the threat..." constitutes an error as well as opposed to "among them the threat..." in D.
Appreciate your kind response.