问题补充:
by the advances in technology, many farmers have set up wind farms on their land.
A. Being encouraged
B. Encouraging
C. Encouraged
D. Having encouraged
答案:
A. Being encouraged
B. Encouraging
(答案→)C. Encouraged
D. Having encouraged
解析:
C。根据句意和空格后的介词by短语可知,空格处应填一个表被动意义的选项,故可排除B和D;而选项A为现在分词的被动式,除表示被动外还表示动作在进行,与句意不符,故也排除。