单项选择题

《中国居民膳食营养素参考摄入量》推荐怀孕中期铁RNI为()mg/d,UL值为()mg/d。()

A.24mg/d;42mg/d
B.26mg/d;42mg/d
C.28mg/d;44mg/d
D.30mg/d;44mg/d