US Bancorp Holds a Press Conference to Announce a Positive

Multiple Choice

U.S. Bancorp holds a press conference to announce a positive news event that was unexpected to the market. As soon as the announcement is made, the stock price increases $8 per share but then over the next hour the price continues to increase resulting in a total increase of $11. Given this information which of the following statements is correct?

A) This is an example of a market overreaction.
B) This is an example of a market underreaction.
C) This is an example of a semi-strong efficient market.
D) None of these statements are correct.