It's becasue human populations are concentrated in areas that are lacking proper resources.
1. Pack a first aid kit, Water, and snacks
2. Try looking at the map, read the riddle, and think about the placethat they are talking about!
3. I say don't worry about "WHERE?" the adventure it's self is the mystery.
4. HAVE FUN!
Deforestation, that would be clearing the land leading to desertification
<span>The greenhouse effect increases temperatures on Earth. ... of the planet's heat that would otherwiseescape from the atmosphere out to space. ... The difference between the Earth's actual average temperature 14° C (57.2° F) and ... of the sun's energy with greenhouse gases such as carbon dioxide, methane, ... Water vapor.</span><span>
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I believe that would be B