Answer:
The correct answer is letter "B": historical prices.
Step-by-step explanation:
American Economist Eugene Fama (born in 1939) proposed the Efficient Market Hypothesis (EMH) stating that it is impossible to beat the market. There are three types of EMH: The Weak, Strong, and Semi-Strong EMH. The Weak form of the EMH suggests that current stock prices reflect all the data of past prices and technical analysis is useless to predict stock price fluctuations.