问题
单项选择题
Which of the following describes the rationale for administering vitamin K to every neonate（）
A. Neonates don’t receive the clotting factor in utero.
B. The neonate lacks intestinal flora to make the vitamin.
C. It boosts the minimal level of vitamin K found in the neonate.
D. The drug prevents the development of phenylketonuria (PKU).
答案
参考答案：B
解析：
Neonates are at risk for bleeding disorders during the 1st week of life because their GI tracts are sterile at birth and lack the intestinal flora needed to produce vitamin K, which is necessary for blood coagulation. Vitamin K stimulates the liver to produce clotting factors. Vitamin K doesn’t prevent PKU, which is an inherited metabolic disease.