Atoms are the smallest unit.
Linked genes are genes that are likely to be inherited together because they are physically close to one another on the same chromosome. During meiosis, chromosomes are recombined, resulting in gene swaps between homologous chromosomes.
It's where something is wrong with the lung and they switch it out for another lung.
The answer is: [C]:
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"<span>because dead animals that fall into water are more likely to be in conditions that allow fossilization" .
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