新加坡公民主要以4大族群来区分，（）占了人口的74.2%。
A.马来人
B.华人
C.印度人
参考答案：B
According to some research, men visit the doctor less frequently over their life times than women. And they have a shorter life expectancy.
中枢性疼痛的部位可覆盖躯体大部分，亦可局限在很小的区域。
