Final answer:
NK cells are derived from CLP (Common Lymphoid Progenitor) cells, which are a type of lymphoid stem cell responsible for the development of lymphocytes involved in the immune response, contrasting myeloid stem cells which produce other formed elements. The correct answer is 1.
Step-by-step explanation:
From the options given, NK cells are derived from CLP (Common Lymphoid Progenitor) cells. Natural Killer (NK) cells are a type of lymphocyte that are part of the innate immune system. They have the ability to recognize and kill virus-infected cells and cancer cells without the need for prior exposure. These cells originate from lymphoid stem cells, which is a type of hematopoietic stem cell that gives rise to all lymphocytes, including T cells, B cells, and NK cells. Contrary to myeloid stem cells, which give rise to other formed elements like erythrocytes and platelets, lymphoid stem cells are dedicated to producing the cells that function primarily in immunity. Therefore, natural killer cells are not derived from CMP (Common Myeloid Progenitor) cells. The correct answer is 1.