Answer:
Part 1:
The four astronomical bodies one could choose to represent the 4 labels in the diagram are
A - universe
B - galaxy
C - solar system
D - Mars
The universe contains galaxies and galaxies holds solar systems which have planets like Mars
Part 2: D or a planet like Mars is unlike all their other astronomical bodies it does not have other astronomical bodies within it thus, its different from rest.
Blood cells are produced in the bone marrow and the bone marrow is part of the skeletal system. So the answer would be skeletal system<em>. </em>
The two lower leg bones are called the tibia and the fibula
