5.A.
1. Weather has been forecast more accurately by people nowadays.
2. Animals should be cared by children.
3. Nuclear weapons must not being tested by countries.
4. Water in the rivers must not be poisoned by factories and plants.
5. Environment should be kept clean by humans.
6. Waste should not be dumped into lakes, rivers and seas by people.
7. Endangered animals and plants ought to be saved by us.
8. Climate should not be influenced so much by man.