Ahh k12 sucks :/ been there but your answer is A !
Answer:
Mesolithic era
Explanation:
The Mesolithic era refers to the middle stage of the stone age i.e. between the Paleolithic and Neolithic. The Paleolithic refers to the old stone age and the Neolithic refers to the new stone age. During this time, the microlithic tools and other attacking weapons were made by the early humans, and also there occurred changes in their way of settlement as the climate and geography changed significantly.
The Mesolithic era started about 8000 years to 2700 years back in the past, in the northwestern part of Europe.
Thus, the Mesolithic era occurred when Europe occupied the present landscape, in terms of climate, biology, and geography.
It is D:canyons It does not tell you why it is Canyons! I hope this has helped you!!!
This occurs when high and think cirrus clouds are above you.