Which answer best illustrates evolution by natural selection? (2.9 points)
A. Ancestors' legs grew longer from climbing to escape predators.
OB. Ancestors that had longer legs could not produce more offspring.
O c. Ancestors wanted longer legs to escape predators and therefore grew longer legs
OD. Ancestors with longer legs escaped predators more easily and lived to produce more offspring.

Define the apical impulse and describe its normal location, size, and duration. which abnormal conditions may affect the location of the apical impulse? explain the mechanism producing normal first and second heart sounds. describe the effect of respiration on the heart sounds. describe the characteristics of the first heart sound and its intensity at the apex of the heart and at the base. describe the characteristics of the second heart sound and its intensity at the apex of the heart and at the base.