55. A serious study once found that people with two cars live longer than people who own only one car. Owning three cars is even better, and so on. There is a substantial positive correlation between number of cars x and length of life y. Which of the following statements is most likely true concerning the study reported above? A The study shows that every person who owns five cars will live longer than a person who owns only two cars. B. The study suggests that we should buy several cars if we want to live longer. C. The study shows that it is clear that owning several cars causes a longer life. D There is a lurking variable, probably wealth, that affects both the number of cars owned and the longer life. Wealthier people can afford to buy more cars, and they also tend to take better care of themselves