The correct option is B Autoimmunity
The immune system in humans works efficiently. It can recognise ‘self’ and ‘non-self’ proteins in the body. Sometimes, the immune system’s mechanisms for detecting non-self sometimes go awry, and normal cells get targeted. This error in profiling is the cause of a long list of autoimmune disorders, including lupus, rheumatoid arthritis etc. The reaction of the immune system against self proteins can be considered as a mistaken allergic reaction called autoimmune disorders.