What is true about the study of 1,000 people born in 1920
A.It shows working is also good for people’s physical health.
B.The participants were tracked over a 14-year period and then investigated at 70.
C.Retirees will live another 12 years if they keep on working.
D.It finds the 70-year-olds would increase by 2.5 times to be alive at age 82 if they kept working.