治疗虚劳脾胃阴虚者，应首选：（ ）
A．玉女煎
B．益胃汤
C．沙参麦冬汤
D．麦门冬汤
E．一贯煎
参考答案：B
Which reason for purchasing U. S. Treasury securities is least valid（）
A. Coupon strips synthesize a zero-coupon bond.
B. Treasury-bonds are available in maturities of two years to nearly 30 years.
C. Treasury Inflation Protection Securities (TIPS) raise their principal value to adjust for inflation.
