1. Correct Answer: D: I, II and III
 
 2. Explanation of Statements:
 
     ● Statement I is correct:  
           ○ Monoclonal antibodies are indeed man-made proteins.
           ○ They are created in laboratories using recombinant DNA technology.
           ○ These antibodies are designed to mimic the immune system's ability to fight off harmful pathogens.
           ○ They are engineered to bind to specific antigens, which are unique molecules on the surface of pathogens or diseased cells.
 
     ● Statement II is correct:  
           ○ Monoclonal antibodies can stimulate immunological function.
           ○ They work by binding to specific antigens, which can neutralize the pathogen or mark it for destruction by other immune cells.
           ○ This binding can block the pathogen's ability to infect cells or can trigger an immune response to destroy the pathogen.
           ○ They are used in various therapeutic applications, including cancer treatment and autoimmune diseases, due to their specificity.
 
     ● Statement III is correct:  
           ○ Monoclonal antibodies are used in treating viral infections, including emerging viruses like the Nipah virus.
           ○ They have been developed as therapeutic agents for several viral infections, providing targeted treatment options.
           ○ In the case of the Nipah virus, monoclonal antibodies can help neutralize the virus and prevent it from spreading within the host.
           ○ Their use in viral infections is part of ongoing research and development to combat infectious diseases effectively.