Ⅰ型糖尿病的病因与下列哪项无关（）
A.病毒感染
B.于自身免疫反应有关
C.遗传因素
D.肥胖
E.化学毒素
参考答案：D
_______ a pair of compasses, it is easy to describe a circle.
A．Having
B．To have had
C．If you have
D．if having
4G全国套餐存费送费合约与3G套餐存费送费保持一致（）
