善于治疗膏淋的药物是（）。
A.滑石
B.萆薢
C.石韦
D.车前子
E.海金沙
参考答案：B
Which of the following relationships most accurately describes the inefficiency resulting from government imposed production quotas（）
A. Marginal benefit exceeds marginal cost leading to underproduction.
B. Marginal benefit exceeds marginal cost leading to overproduction.
C. Marginal cost exceeds marginal benefit leading to overproduction.
润滑系有哪四大功能？
