None of the above? I’m guessing, secondary, primary and tertiary doesn’t sound right !
<span>Human weight at the time of birth is influenced by stabilizing selection. Stabilizing selection, also known as negative selection, purifying selection or normalizing selection, is a type of natural selection in which genetic diversity decays according to a particular value of the character. This is the most common mechanism of action of natural selection.</span>
Elbows and knees would be the answer