GMAT Sentence Correction (SC) | Re: The world wildlife fund has declared that global warming, a

This explaination seems wrong, how can fossil fuels can cause global warming. Its the burning of fossil fuels by humans so we can say that global warming is caused by human beings by burning of fossil fuels. Also apostrophe with any noun in Gmat is used only when that thing literally belongs to that noun. But here it doesent so D seems legitimate