Once the economic and social usefulness of the motor car was demonstrated and with its superiority to the horse being proved, much of the early hostility to it in rural regions disappeared.
(A) and with its superiority to the horse being
(B) and its superiority over the horse had been
(C) and its superiority to the horse
(D) its superiority over the horse
(E) with its superiority to the horse having been
BY给的答案是B,大全的答案是C. 我认为是B, B的时态也能说过去,而且和前面从句对称.而C名词短语和前面不对称. | 
