The Western world's leading cause of early death is ______.

A．A diet that is sugar free but nutrient-rich.
B．A diet that is sodium free but vitamins-rich.
C．A diet that contains a lot of potassium and calcium.
D．A diet that consists of low-fat meat and fresh plants.

A．aerobic exercise help prevent lung diseases
B．vigorous exercise is dangerous for poeple over 50
C．weight lifting can do much good to the frail elderly
D．the more exercise one does, the less one is likely to die