Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the option that bestfits each of the numbered blanks from 18 to 22. .

Earth Hour is a movement organized by the World Wildlife Fund (WWF). ___(1)___. It encourages people and businesses to turn off their lights and other non-essential electrical devices, for an hour from 8:30 to 9:30 p.m on the last Saturday of March. The initiative was proposed in 2004 in Australia, but the idea of a worldwide movement ___(2)___. Earth Hour was started as a lights-out event in Sydney, Australia, in 2007. Since then, it has grown to become an international movement for the environment, ___(3)___. Later in October 2007, a similar event called “Lights Out” was held in San Francisco.
Due to the success of the event, the organizers decided to hold Earth Hour annually around the world. ___(4)___. More importantly, it has helped raise awareness of climate change and has become a symbol of our commitment to protecting our planet. Although one hour can’t change the world, it encourages governments and people to set long-term goals for sustainable development around the world.
Joining the event in 2009, ___(5)___. Besides switching off lights, people can take part in a number of activities to raise awareness of environmental problems and call for action for climate, people and nature.