It was problem that of the students could work it out.
A. so hard a ; a few
B. such a hard ; few
C. such hard a ; few
D. so a hard ; a few
网友回答
A. so hard a ; a few
(答案→)B. such a hard ; few
C. such hard a ; few
D. so a hard ; a few
解析：本句符合句式：such +a+adj+n，后一空用否定词，符合题意，故选答案为B