问题
单项选择题
Which of the following statements about trading shares of stock or market efficiency is FALSE（）
A. Maintenance margin is the required percentage of an investor’s equity compared to the total value of the stock after the investor trades on margin.
B. The up tick rule requires that the last trade in the security be at a price higher than the previous trade.
C. External efficiency means prices adjust rapidly to new information.
答案
参考答案：B
解析：
The up tick rule requires that either: (1) the last trade is at a price higher than the previous trade, or (2) the last trade is at the same price (a zero trade) and that the previous non-zero trade is at a price higher than the trade before it.
