I believe it is C but not sure.
A mutation is a genetic error in the creation of DNA. My science teacher compared it to a copier that made a mistake; the DNA is copied from others, but the "copier" messed up, making part of a helix different. Mutations can be genotypes or phenotypes.
Alec Jeffreys is a professor at the university of Leicester. and discover DNA typing in the UK .
Answer: I think the answer is true
Explanation: If you think about it, the terrestial planets ( being venus, earth, mars, and mercury) are made up very little gas which are carbon dioxide, nitrogen and oxygen, and the gas giants ( being jupiter, saturn, neptune, and uranus) have gases such as hydrogen and helium. Thus meaning, the terrestial planets could be a part of it and the gas giants are the most. So yes, the answer is true.
Answer: Option D) there are no holes for blood to enter or leave the system
The human cardiovascular system is considered closed because there are no holes for blood to enter or leave the system
Explanation:
The closed circulatory system are made up of blood vessels called arteries from the heart that branch into small units called capillaries but eventually join up with other blood vessels called veins that are connected to the heart. So, blood is always confined to circulate within the blood vessels and the heart as there are no holes for blood to enter or leave the system
Thus, the human cardiovascular system is considered closed