Which substance do we consider to be the elementary unit of life?
a. dna
b.protein
c. red blood cells
d. white blood cells
e. chromosomes

a. DNA is the correct answer

Explanation:

because DNA is the controller of everything

D. None of the above

Explanation:

Reason that Drastic Change in weather may cause mass extinction

Weather plays an important role in the survivability & the growth/diminish of the population. For example, animals that need large amounts/bodies of water (for example fishes), will not survive when the area is hit with a heat wave & drought, which would cause fishes to surface, and die.

Reason that Geological change would play a large role in mass extinctions

While the Geography is constantly changing, large abrupt changes would cause a upheaval and may upset the population, leading to a depletion of resources or even a sudden destruction of part/all of the population. For example, an earthquake may kill large amounts of animals, and the destruction of the greenery in the area may severely limit the amount of food/decrease the primary consumer's populations, leading to a starvation.

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