Suppose the fundamental value of stock could be $100 or $120 per share. Suppose your information leads you to expect that the fundamental value is $100, but you are not sure. Suppose you observe that the price of the stock reaches $110 per share. As a result, you decide to buy the stock and now expect its price per share to rise to $120. You have experienced

A. a regression result

B. an information cascade

C. the efficient markets hypothesis

D. a random walk