儿童饮食中碳水化合物供热比例应为
A.12%~15%
B.16%~20%
C.25%~35%
D.45%~50%
E.55%~65%
参考答案:E
— Let's try operating the machine right now.
— Wait. Better read the _____ first.[ ]
A. instructions
B. explanations
C. information
D. introduction
简述维生素B缺乏症的临床表现。