Briefly explain why variable regions of immunoglobulin are involved in microbial antigen recognition?

The variable regions of immunoglobulins contain antigen-binding sites that are highly specific for recognizing and binding to microbial antigens. These regions are responsible for the diversity of antibodies and their ability to recognize a wide range of antigens. By binding to microbial antigens, antibodies can neutralize pathogens, mark them for destruction by immune cells, and initiate an immune response against the invading microbe.