Final answer:
The secondary response involves a more rapid synthesis and increased titer of antibody upon subsequent exposure to the same antigen, utilizing memory B cells to produce higher levels of IgG antibodies with greater affinity. The answer is option C.
Step-by-step explanation:
The process that involves more rapid synthesis and a greatly increased titer of antibodies when the immune system is subsequently exposed to the same antigen is known as the secondary response. This response occurs after the immune system has already been exposed to the antigen once, allowing the immune system to react more quickly and efficiently upon subsequent exposures. The primary response, in contrast, is the immune system's initial reaction to a new antigen, which is slower and produces antibodies at lower levels.
During the secondary response, memory B cells that were generated during the primary response quickly recognize the antigen and proliferate, differentiating into plasma cells that produce high levels of IgG antibodies. These antibodies have a higher affinity for their specific antigens, and their levels remain elevated longer than during the primary response, providing enhanced immune protection.