A logical answer is because higher up there is more exposure to the sun heat rayes.
I would say Spruce because they don't reproduce A-sexually like the other 3 options.
Ophthalmology is the specialty dealing with disorders and injuries of the eye... And ophthalmologist is the specialist responsible. Do not confuse with a optometrist. An optometrist only does basic diagnosis and fitting for eye ware.
They each have their own part, position, and abilities.
Answer:
Mutation
Explanation:
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