<span>Stabilizing selection is at work in this case. This is the force that allows a population to gradually center on a mean value due to a presence of a non-extreme bodily trait. The more extreme examples of the trait lead to the organisms being selected out, and the trait that is the least conspicuous wins out in the long-run.</span>
Baroreceptors. These are found in the carotids and aortic arch. They respond to pressure exerted on the vessels.
B, Rhizoids.
That's the only one that won't help you in a tough spot!