According to Li Shangfu, ______ director of the Xichang Satellite Launch Center, ______ launch of China’s first lunar probe Chang’e-1 was ______ success.
--- Never before in China ______ for the farmers.
--- You’re telling me. They extremely content with the new farming policies.
A. had so much been done C. so much has been done
C. has so much been done D. has done so much