The answer of your question
a. A shared ancestral character.
Explanation:
The condition of birds and mammals having four limbs is a shared ancestral character because the structure of the limbs are similar in both the cases.
The forelimbs of the bird are modified into wings to aid flying.The hind limbs are modified into feel and claws.
These are homologous structures to the hands and feet in mammals.
That means they have a common origin, and hence are shared ancestral character.
Answer:
<u>C. Earth</u>
Explanation:
I would say <u>Earth</u> because it can be rocky, it has mountains and valley, and of course, the Earth has a crust. And, it revolves around the Sun. Moon, may be rocky, but it doesn't have mountains or valleys. And it doesn't revolve around another body in the solar system. And of course, we all know the sun isn't rocky, and it doesn't have mountains or valleys. That's why my answer is <u>C. Earth</u>.
Answer:
One sample should have had no enzyme and acted as a control.