The average life expectancy of a population is an important indicator of the health level of a country and region. The sixth national census showed that the average life expectancy of China's population in 2010 reached 74.83 years, while the average life expectancy of our population in the early days of the founding of our country was only about 35 years. The elderly people thought more than 60 years ago now seem to be just middle-aged people. Which of the following, if true, would most weaken this view. ["Since the founding of the People's Republic of China, the decline in the number of newborn babies has been the most important cause of the increase in the average life expectancy of the population.", "In the early days of the founding of the People's Republic, the country was moving from war to peace, the situation in the country was still unstable, and the population was much lower than it is now.", "In the early days of the founding of the People's Republic of China, the living environment was harder and people's nutritional levels were much worse than now.", "With the development of medicine, the level of medical care has greatly improved compared with the early days of the founding of the People's Republic of China."]