(1)These are the topics in the index pages .Which group in t

(1)These are the topics in the index pages .Which group in the correct order
A Fish,Ants ,Habits,Sharks B Bread,Jungles,Traffic,Weather
C Parks,Environment,Eggs,birds D Trees,Litter,Farming,Glass
(2)Trees can cool the air.Trees can clean the air.(同义句转换)
Trees can cool the air and clean it _____ ＿＿＿＿．