D. This is to “proofread” the DNA
Explanation:
Since lice feed on human blood, severe and chronic infestation can lead to blood loss and iron-deficiency anemia. 5 In addition, an allergic reaction to louse feces or bites may trigger a rash in some individuals.
No beacuse the other layer may be to cold or hot for humans to survive in
The earth may be covered by many plants and have more water resource,fresh air,and natural resources than now because their is no any pollutant that can pollute the air water and soil so there may not be any kind of pollution and also there is more plant resource than now because now a day's most forests and plant vegetations are cuted down to make houses and also huge factories.
Can you add me as the brainleist please?