According to a 1995 World Health Organization survey report, 70% of lung cancer patients have a history of smoking, 80% of whom have a history of smoking for more than 10 years, which shows that smoking increases the risk of lung cancer. Which of the following best supports this assertion? ['The number of male smokers increased rapidly during the period from 1950 to 1970, and the number of female smokers also increased.', 'Although countries have vigorously promoted the harmful effects of smoking, the proportion of smokers has increased significantly since the 1950s. By the 1990s, adult smokers had reached 50% of the adult population.', 'The number of people who have no history of smoking or have quit smoking for more than five years exceeded 40% of the total population in 1995.', 'The number of underage smokers also increased in 1995, becoming a social problem.']