Final answer:
Color Doppler displays both peak flow velocity and flow direction, with different colors representing different velocities, aiding in the visualization of blood flow through constrictions in vessels.
Step-by-step explanation:
Color Doppler is a type of Doppler ultrasound that can provide visual information about blood flow within a vessel, such as an artery. It does this by using different colors to represent the direction and the velocity of blood flow. According to the descriptions provided in the figures, higher blood velocities are represented in red, whereas lower velocities are shown in blue. The specifics of Doppler images would tell us that option B) Peak flow velocity and flow direction are displayed. When there is a constriction in an artery, blood moves faster to maintain the flow rate, leading to higher peak velocities at or nearby the constriction, and Color Doppler can effectively visualize this phenomenon.