A-A+
A new technique ______ the yields as a whole
问题详情
A new technique ______, the yields as a whole increased by 20 percent.
A．working out
B．having worked out
C．having been worked out
D．to have been worked out请帮忙给出正确答案和分析，谢谢！
参考答案
正确答案：C
解析：本题考分词的独立结构作状语的用法。结合语态，故C项正确。本句大意为：新技术研究出来之后，整个产量增长了20%。
