It's simple. Let's go back. The answers are A and 8050, which means that the futures market gains 8950-8050=900 (yuan/ton), the spot market loses 8800-7950=850 (yuan/ton), and the overall profit is 8850-8800=50 (yuan/ton). Besides, your mind has reached a dead end. The spot market has lost money in 850 yuan, and the futures market must be profitable in 850 yuan. The problem is that if the manufacturer finally makes a profit in 50 yuan, then the futures market must make a profit of 850+50, that is, 900 yuan can make the manufacturer make a profit in 50 yuan, while the futures market makes a profit in 900 yuan, so the transaction price in the futures market is 8950-900=8050, that is, the futures market must close at 8050.