All sources of pollution come from human activities.

Yes because humans are the one who plays the important role in every resources.without human resource everything would be meaningless. by their activities they destroy the natural resources like air,land ,water etc., by implementing new technologies which would be the main threatening feature of the environment 

The answer would be Yes, because humans, their playing the important roles. We have resource, if we didn't have resource we wouldn't be able to know what to do. For example, it would be meaningless if we didn't have resources to help us.