The Three women, liberal activists who strongly support legislation in favor of civil rights and environmental protection, have consistently received labor’s unqualifying support.

A. have consistently received labor’s unqualifying support

B. are consistently receiving the unqualifying support of labor

C. have consistently received the unqualified support of labor

D. receive consistent and unqualified support by labor

E. are receiving consistent and unqualified support by labor

正确答案是A，可是这里one’s所有格没有问题吗？为什么C不对？unqualifying 和 unqualified有什么区别？另外，这里用现在完成时，是不是因为有consistently为标志？