Which process involves displaying processed antigens on the surface of antigen-presenting cells?

The chosen answer is correct because antigen presentation is the specific process by which antigen-presenting cells (APCs), such as dendritic cells, macrophages, and B cells, process and display antigens on their surface. This is a crucial step in the immune response, allowing the APCs to present these processed antigens bound to major histocompatibility complex (MHC) molecules to T cells.

When an APC encounters a pathogen, it engulfs and digests it, breaking it down into smaller peptide fragments. These fragments are then loaded onto MHC molecules, which transport the antigens to the cell surface. This presentation is vital for T cell activation, as T cells rely on recognizing these specific antigen-MHC complexes in order to initiate an immune response.

In contrast, viral infection refers to the process by which a virus enters and replicates within a host cell, not specifically related to the display of processed antigens. Phagocytosis is the process by which cells like macrophages engulf and destroy pathogens but does not directly involve displaying antigens. Antibody formation is the process by which B cells produce antibodies in response to an antigen; however, it does not pertain to the presentation of processed antigens by APCs to