What do we know about the study of 1,000 people aged 70
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 vears if they keep on working.
D. It finds the 70-year-olds would live another 2.5 years if they kept working.