2 and 3 are too similar to distinguish because they both are saying it's been back up on several different accounts but 3 seems like a more solid answer go with 3
The amount of water on the planet is fixed; it neither increases or decreases. Glaciers are sheets of moving ice. This water to form these extensive sheets must come from somewhere. The water comes from the most extensive store on the planet; the oceans. Ice Ages always corresponds to periods of low sea level because much of the ocean water is is land locked as glaciers.
Answer:
Natural selection
Explanation:
Natural selection occurs when one allele (or combination of alleles of different genes) makes an organism more or less fit, that it is able to survive and reproduce in a given environment. If an allele reduces fitness, its frequency will tend to drop from one generation to the next.
Answer:
Release carbon into the atmosphere through respiration
Explanation:
During cellular respiration the molecule takes in oxygen and glucose. ... Pyruvate is transported into the mitochondria and loses carbon dioxide to form a two-carbon molecule.