He diagram shows the leg bones of a (left -> right): orangutan, dog, pig, cow, tapir, and horse. most of the animals have the same bones, although some are shaped differently and placed in different positions.

what does this suggest about mammals?
a) that they shared a common ancestor.
b) that mammals are evolving to become more and more like one another.
c) that they developed their bone structure independently of one another.
d) that the shape of the bones has less to do with the environment pressures on the animal, and more to do with what their relatives are.

The correct answer is A. That they shared a common ancestor

Explanation:

In evolution, similar structures such as bones, organs, etc. in different species are often classified as homologous structures, this implies different species or organisms share a common ancestor and therefore there are similarities between them, but also differences as each species needed to adapt to different environmental conditions and evolved in different ways over time. This leads to structures that are similar but not identical and might differ in function, which occurs in the case of the leg bones of orangutan, dog, pig, etc. that are all mammals deriving from the same ancestor and thus share similar leg bones but with specific features or differences. Thus, the diagram suggests that mammals share a common ancestor.

i think it would be b. tissue because an organ system is a group of organs that work together to perform one or more functions. each does a particular job in the body, and is made up of certain tissues.