Which is an example of a renewable resource ? a. forests b. coal c. oil d. natrual gas, i think the answer is d?

A) forests are a renewable resource. Trees can be replanted as they are being cut down, though I'm pretty sure it's not good for the soil. :)
Coal and oil both are fossil fuels and so take a long time to be created. It takes too long for it to be created for us to use it a lot.
Natural gas is still a non renewable resource, it's just cleaner for the air than the other two. 
Hope this helps! Please let me know if I'm wrong :)