It's A, because it's always important to drink water. If you think about it, all the other answers seem invalid.
The inner core is responsible of the Earth's A) magnetic fields
Answer:
Destruction of a natural environment is a big threat to the humanity. With the destruction of forests, the wild life is becoming extinct. Lesser number of trees means more harmful gases to be transferred to the ozone layer. Without the ozone layer, the survival of humans on the Earth will be impossible.
If plant or animals become extinct or endangered from a natural environment, this will mean lesser food for the humans. There will be increased competition for food and other resources.
Answer:
1. mutation and genetic recombination
Climate change is most commonly measured using the average surface temperature of the planet.
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