Which one of the following statements is correct?

Group of answer choices

a. If a stock is currently undervalued by the market, marginal investors will sell the stock.

b. If a stock is currently overvalued by the market, marginal investors will buy the stock.

c. If a stock is currently undervalued by the market, its expected return will increase as its price rises in the future.

d. If a stock is currently overvalued by the market, its expected return will decrease as its price drops in the future.