Both of them are the most important cities in their countries. They are capitals and cultural, demographic and industrial centres.
Earth is the 3rd closest.
<span>The Global Surface Temperature is Rising
</span>NOAA states:<span>Many lines of scientific evidence show the Earth's climate is changing. This page presents the latest information from several independent measures of observed climate change that illustrate an overwhelmingly compelling story of a planet that is undergoing global warming. It is worth noting that increasing global temperature is only one element of observed global climate change. Precipitation patterns are also changing; storms and other extremes are changing as well.
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It would be C. Rain. Water is evaporated from the earth into the sky to form clouds. Then it turns into rain that falls to the ground, and this process continues.
I hope this helped if you need a better explanation then ask, and I'll see if I can't provide you with one.