Arrange the following lists in hierarchical order. atoms, dog, liver, digestive system, liver tissue, liver cell, molecule.

Internal gestation followed by live birth is an evolutionary development most likely driven by which of the following? a. the inability of eggs to acquire nutrients to grow complex animals b. the need to give birth and reproduce on dry land where eggs could dry out c. the threat of predators to eat eggs d. environmental conditions caused eggs to over-absorb dangerous molecules from the environment