PTE Reading MC Single Answer: Every day millions of lights and computers are left on in deserted offices, apartments,…

Every day millions of lights and computers are left on in deserted offices, apartments, and houses. Environmental activists say that simply switching them off could cut Sydney's greenhouse gas emissions by five percent over the next year. Per capita, Australia is one of the world's largest producers of carbon dioxide and other gases that many scientists believe are helping to warm the Earth's atmosphere, causing climate upset. A long-standing drought and serious water shortages in Australia have focused much attention on climate change. Some experts warn higher temperatures could leave this nation of 20 million people at the mercy of more severe droughts and devastating tropical cyclones.