The so-called hungry marketing refers to the marketing method that the merchandise seller intentionally reduces the sales volume in order to achieve the regulation of supply and demand, create the illusion of oversupply, and maintain a higher price and profit rate of the product. Hungry marketing can also achieve the maintenance of brand image and increase the added value of products the goal of. Based on the above definitions, Which of the following are used by hunger marketing:. ['Merchants discount sales of seasonal products.', 'When a real estate agent launches a new property, the price is intentionally increased.', 'A mobile phone brand has a limited sale on the first day of launching a new product.', 'A hospital stipulates that the number of registered outpatients for experts is limited to 30 people per day.']