A: The so-called hedging refers to the offsetting financial operation taken by investors to prevent adverse price changes. Its usual practice is to buy and sell in two opposite directions in the spot market and the futures market, so that the profits and losses of the two markets are roughly balanced, thus achieving the purpose of preventing risks. Suppose someone expects to have an income in three months, and he is going to use this income to buy short-term government bonds. But he is worried that the interest rate of national debt will fall in three months (which means that the price of national debt will rise), which will make him suffer losses. At this time, he can buy a certain amount of treasury bonds futures first. Assuming that the interest rate really falls after three months, he will lose money in the spot market, because after the price of national debt rises, the number of bonds he can buy will decrease; But this loss can be made up in the futures market. Because at this time, the price of bond futures will also rise with the rise of spot price, which will bring him a certain spread income.