Which of the following is not an advantage of a repurchase? a. a repurchase announcement may be viewed as a positive signal by investors because repurchases are often motivated by managements' belief that their firms' shares are undervalued. b. stockholders are often indifferent between dividends and repurchases, and repurchases are generally just as dependable as dividends. c. stockholders have a choice when the firm distributes cash by repurchasing stock—they can sell or not sell their shares. d. repurchases can be used to produce large-scale changes in a firm's capital structure. e. a repurchase can remove a large block of stock that is "overhanging" the market and keeping the price per share down.