The correct answer is (d) It is smaller and does not give shape to the animal cell.
Animal cells have smaller vacuoles as compare to that of plant cell. It does not decides the shape of the of the animal cell. The main function of vacuoles in animal cell is endocytosis and exocytosis. They store the waste material. In plant cell the vacuoles cover almost 90% of the space and decides the shape of the plant cell as they are filled with water. This helps the plant cell to maintain turgor pressure.
D - spine alignment and foot size.
Late australopiths had an S-shaped spine that allowed for balance when standing. Shorter and less flexible toes made pushing off the ground much easier.
Your answer is hypothesis i think. There were no given answer choices so i went with what i think youre asking.