182.
The organic food industry has organized a successful grassroots campaign—using Web sites, public meetings, and also mass mailings—that have convinced the Department of Agriculture to change the proposed federal regulations for organically grown food.
A. using Web sites, public meetings, and also mass mailings—that have convinced
B. using Web sites, public meetings, and mass mailings—that has convinced
C. by using Web sites, public meetings, and mass mailings—in convincing
D. by the use of Web sites, public meetings, as well as mass mailings—that convinced
E. which used Web sites, public meetings, and mass mailings—in convincing
请教这题为什么要用完成时态？ D为什么不好？ 难道因为as well as不如and好吗？ | 
