Which of the following components of blood is collected during apheresis?

The correct choice is specific blood components, as apheresis is a specialized procedure that allows for the selective collection of specific components of blood. During apheresis, the blood is drawn from the donor, processed through a centrifuge or similar device to separate its components, and then only the desired component (such as platelets, plasma, or leukocytes) is collected, while the remaining components are returned to the donor.

This technique is widely used in blood banking to efficiently collect high yields of specific components that can be critical for treatments, such as platelet transfusions for patients undergoing cancer treatment, or plasma donations for patients with liver disease. The flexibility of apheresis allows for targeted collection, addressing specific patient needs while ensuring donor safety.

In contrast, whole blood refers to blood in its entirety, which is not specific to any component and is typically collected for general transfusion purposes rather than specialized processing. Moreover, stating that only plasma or only red blood cells are collected does not encompass the full capability of apheresis, which can extract multiple types of blood components depending on the need and equipment used. Thus, apheresis's primary function is to collect specific blood components based on therapeutic requirements.