Which of the following statements about selling shares of stock is FALSE（）

A. The "depth" of the market is typically defined as the number of traders willing to trade at prices above and below the current price.

B. If the initial margin requirement is 50% and the maintenance margin requirement is 25%, the investor who buys a stock at $26 on margin will receive a margin call when the stock hits $17.33.

C. Initial public offerings are sold in the secondary market.

毛细支气管炎可出现（）

A.脓胸／脓气胸

B.支气管扩张

C.肺脓肿

D.胸腔积液

E.肺气肿