Final answer:
The correct answer is (a) Ventricular filling and aortic elastic recoil, which describes the process during the ventricular diastolic phase where the ventricles are filled with blood while the pressures in the heart adjust.
Step-by-step explanation:
The ventricular diastolic phase is associated with ventricular filling and aortic elastic recoil. This phase follows the closure of the semilunar valves, which occurs when the pressure inside the ventricles falls below the pressure in the aorta and pulmonary trunk. This closure prevents backflow into the heart and is signified by a dicrotic notch on blood pressure tracings. At the start of ventricular diastole, the atrioventricular valves are also closed, meaning there is no change in the volume of blood in the ventricles; this part of the phase is known as the isovolumic ventricular relaxation phase.
During the subsequent phase, the atrioventricular valves open, allowing blood to flow from the atria into the ventricles, thus contributing to ventricular filling. Hence, the correct answer is (a) Ventricular filling and aortic elastic recoil, which describes the overall process of ventricular diastole.