Option (B) is correct because the textbook explicitly states that 'Stem cells are present in most of the multi-cellular organisms.' The context further explains that stem cells are found in humans in locations such as the umbilical cord, placenta, inner cell mass of the early embryo, tissues of the foetus, and some adult organs. Stem cells are undifferentiated cells capable of self-renewal and differentiation into specialized cell types, which is a characteristic relevant to multicellular organisms that have various tissues and organs. Unicellular organisms, non-living things, and viruses do not possess stem cells as they lack the complex multicellular structure and tissue systems that stem cells are designed to maintain and repair.