问题详情

The association between ______ has not yet been found in Australia.
A．ozone levels and hospital admissions for asthma
B．hazy days and more asthma attacks in children
C．the levels of particles in the air and death rates
D．high levels of pollution and more symptoms此题为多项选择题。请帮忙给出正确答案和分析，谢谢！