Now investing in the gold sector will be a profitable business activity. A survey by China Gold magazine revealed that 88% of the magazine's readers are planning to buy a batch of gold bars recently, while investing in gold Market research shows that the gold bullion purchase and redemption business currently launched each year can only meet 70% of the purchase demand. Which of the following, if true, would most question the correctness of the investment proposal above? ['About half of those who buy gold bars make mortgages to buy gold bars.', 'In the first two weeks of the bullion purchase and redemption business, the bullion bar sold only 20% of the total.', 'About half of the people who bought gold bars have ever invested in gold.', 'Only 20% of those who claimed to buy gold bars actually bought them.']