Latent demand refers to a demand situation in which a considerable number of consumers have a strong demand for a certain product or service, but cannot be met by existing products or services. According to the above definitions, Which of the following can best embody the "latent demand":. ['Most of the real estate sold in a city are three-bedroom large units, which makes workers who want to settle down here discouraged.', 'A traditional Chinese medicine hypoglycemic health product launched by a pharmaceutical company can replace medicines to some extent, often in short supply.', 'It is unclear how effective radiation protection maternity wear on the market is against electronic products.', 'The new type of video game machine with eye protection function, presumably can convince some parents of students to come to buy [weibo].']