Which of the following is true?
A) A random walk for stock price changes is inconsistent with observed patterns in price changes.
B) If the stock market follows a random walk, price changes should be highly correlated.
C) If the stock market is weak form efficient, then stock prices follow a random walk.
D) All of these.
E) Both If the stock market follows a random walk, price changes should be highly correlated; and If the stock market is weak form efficient, then stock prices follow a random walk.