Statement: 

European economy is dependent mainly on forests.

Conclusions:

(I) Europe wants only maintenance of forests to improve economic conditions.

(II) Trees should be preserved to improve the Europe economy.

Which conclusion will follow on the basis of given statement?

Only Conclusion II follow

It is clear from the statement that European's economy depends mainly on forest and from conclusion II, we can say trees are the part of forest. Hence, Trees should be preserved to improve the Europe economy.

But from conclusion I, ONLY maintenance of forests can improve the economy that can not say. So this conclusion does not follow.