关节结核的早期X线主要表现是（）
A.以骨质破坏为主
B.以骨质增生为主
C.骨质增生与破坏并存
D.局限性脱钙
E.关节间隙消失
参考答案：A
读印度气候图分析回答问题：
（1）图甲为印度旱季，每年 月至 月，盛行风向为 风;
（2）图乙为印度雨季，每年 月至 月，盛行风向为 风。
Which of the following most accurately describes elasticity of supply Elasticity of supply is the percentage change in the quantity supplied divided by the percentage change in:（）
A. price and it equals zero when supply is perfectly elastic.
B. price and it equals zero when supply is perfectly inelastic.
C. quantity demanded and it equals infinity when supply is perfectly inelastic.
