【正确答案】A share of common stock in a firm represents an ownership interest in that firm. Common stockholders vote, receive dividends, and hope that the price of their stock will rise. There are various classes of common stock, usually denoted as type A, type B, and so on. Unfortunately, the type does not have any meaning that is standard across all companies. The differences among the types usually involve either the distribution of dividends or voting rights. It is important for an investor in stocks to know exactly what rights go along with the shares of stock being contemplated. 　　In the event of liquidation, common stockholders have rights to a company’s assets only after bondholders, other debt holders, and preferred stockholders have been satisfied. Typically, common stockholders receive one vote per share to elect the company’s board of directors (although the number of votes is not always directly proportional to the number of shares owned). The board of directors is the group of individuals that represents the owners of the corporation and oversees major decisions for the company. Common shareholders also receive voting rights regarding other company matters such as stock splits and company objectives. In addition to voting rights, common shareholders sometimes enjoy what are called “preemptive rights". Preemptive rights allow common shareholders to maintain their proportional ownership in the company in the event that the company issues another offering of stock. This means that common shareholders with preemptive rights have the right but not the obligation to purchase as many new shares of the stock as it would take to maintain their proportional ownership in the company, also called junior equity.