Answer:
Crossing over is termed as a process by which genetic materials are exchanged by non-sister chromatids during meiosis. Crossing over results in the new combination of information in genetic for, the cell for a specific trait. It ensures that organisms are identical from one generation to another.
Explanation:
I believe that it is the old growth not sure which one but between B and D I would go with B but I am not sure (hope I helped in some way )
A monomer is the basic unit that binds chemically to other molecules to form a polymer .
For lipids, the monomers are glycerol and fatty acids.
This might help you understand
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