Final answer:
Active immunity is advantageous because it leads to the development of immunological memory (option b), lasts much longer than passive immunity, and can protect the body against future infections from the same pathogen without additional doses of antibodies.
Step-by-step explanation:
One reason why active immunity is more advantageous than passive immunity is that active immunity leads to the development of immunological memory. When an individual's immune system is exposed to a pathogen, it not only fights the current infection but also creates memory cells that remain in the body. These memory cells are capable of recognizing the pathogen swiftly if it attempts to infect the body again, thus mounting an immediate and robust immune response. Moreover, active immunity typically lasts much longer than passive immunity; it can last for many years or even for a lifetime, which means the body is equipped to defend itself against certain diseases without needing repeated exposure or additional doses of antibodies.
Active immunity can be acquired two ways: naturally, by an infection that triggers an adaptive immune response and leads to memory; and artificially, through vaccination. Vaccines simulate an infection, enabling the immune system to develop memory without the person having to suffer the symptoms of the actual disease. This contrast with passive immunity, which involves the direct transfer of antibodies or T cells to an individual and tends to last for only a short time, ranging from a few days to a few months, as it does not lead to the creation of memory cells.