持续改进方案对员工来说有何意义？

A. That's very nice of you
B. No, you don't have to
C. Yes, please
D. With pleasure

A. 生活方式与行为
B. 生物遗传因素
C. 医疗卫生服务
D. 环境社会因素

A. 4个
B. 6个
C. 8个
D. 12个