The newly elected baseball commissioner has asked that a federal arbitrator would mediate
negotiations between representatives of the umpire's union, which has threatened to go on strike,
and the lawyers representing major league franchise owners.

A. that a federal arbitrator would mediate negotiations between representatives
of the umpire's union, which has threatened

B. that a federal arbitrator mediate negotiations between representatives of the
umpire's union, which have threatened

C. of a federal arbitrator that he mediate negotiations between representatives
of the umpire's union, which have threatened

D. a federal arbitrator that he mediate negotiations between representatives
of the umpire's union, which has threatened

E. a federal arbitrator to mediate negotiations between representatives
of the umpire's union, which has threatened


OA: E

Why is option D wrong ?