Global climate change is a concern to scientists because
a. is a natural process unaffected by humansb. has never changed beforec. can have drastic effects to life on earthd. can happen overnight

Option C, can have drastic effects to life on earth

Explanation:

Global climate change is occurring at a tremendous rate and is also adversely affecting all life forms including animals, plants and human being

The following climatic changes are happening -

a  ) Rise of temperature of earth by 1-2 degree Celsius every year

b) Melting of glaciers and snow on mountains.

c) Warming of oceans  is adversely affecting the life of aquatic plants and animals

d) Rising sea level is creating a risk of submergence of nearby shore area.

Due to all these pre-predictions, scientist are worried of global climate change

Hence, option C is correct

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