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

A．all HIV carriers are doomed to die
B．only those who show clinical evidence of AIDS will pass on the virus
C．the number of AIDS cases will be reduced in the 1990s
D．IV drug users are a high-risk group vulnerable to AIDS infection

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.