Earth Hour, the voluntary one hour blackout observed by 187 countries on 23rd day of March every year, to mark a battle against global warming, was first organized by which organization of the following:

World Wildlife Fund for Nature

The correct answer is Option (3) → World Wildlife Fund for Nature

Earth Hour, a global movement encouraging people to turn off non-essential lights for one hour as a symbolic stand against climate change and environmental degradation, was first organized by the World Wildlife Fund (WWF, also known as World Wildlife Fund for Nature) in partnership with others in Sydney, Australia, in 2007.