某小孩缺钙,医生建议该小孩服用钙片的同时,还要服用少量鱼肝油,这是因为鱼肝油中含有丰富的( )
A:维生素A
B:维生素B
C:维生素C
D:维生素D
下列标志中属于质量安全标志的是( )
I've read through this book several times,but I will read it so as to get better understanding.( )