prep 1#187 including 是个介词还是伴随状语

187.
            (27622-!-item-!-188;#058&002521)

United States Senator Daniel Inouye was appointed to several posts within the Democratic Party during his first term, that included assistant majority whip and vice-chair of the Democratic Senatorial Committee.

A. that included

B. which includes

C. including

D. some of which were

E. among them being

请问：

用including是做伴随状语还是including是介词？