One in five humans access to safe drinking water by 2080．
A. is said lacking
B. is said to lack
C. are said to lack
D. are said lacking
网友回答
A. is said lacking
(答案→)B. is said to lack
C. are said to lack
D. are said lacking
解析：考查主谓一致。humans指多个民族，谓语动词用单数，be said to do据说……，根据句意选B。