Which of the Following Statements Contrasting Simple and Complex Multicellularity

Which of the following statements contrasting simple and complex multicellularity is TRUE?

A) Complex multicellular organisms show a large degree of cellular differentiation, whereas simple multicellular organisms show little differentiation into specialized cell types.
B) Cell or tissue loss in a simple multicellular organism can be lethal for the entire organism, whereas cell or tissue loss in a complex multicellular organism does not lead to death of the entire organism.
C) Highly specialized molecular mechanisms allow cells to adhere to one another in simple multicellular organisms, but not in complex multicellular organisms.
D) Only some cells are in direct contact with the environment in simple multicellular organisms, whereas all cells are in direct contact with the environment in complex multicellular organisms.
E) Most or all of the cells in a complex multicellular organism contribute to reproduction, whereas only a subset of cells contributes to reproduction in simple multicellular organisms.