钻取混凝土芯样时，直径一般要求不小于集料最大粒径的（）。
A.2倍
B.3倍
C.4倍
D.5倍
参考答案：B
In the context of companies in financial difficulty, explain the meaning, effect and rules relating to the operation of administration as an alternative to winding up. (10 marks)
维生素D缺乏性佝偻病的基本治疗法则是“虚则补之”，其重点在于补肺肾（）
