Student 4 is correct. The farther the planet is from the Sun, the less pull it exerts on it.
The answer is A - stores genetic information I think
A or C
Just choose any of those!
DNA/fingerprints are all unique, therefor it is easy to match a fingerprint to a person thus they use this mechanism in criminal investigations because only one person woul have matching DNA to the prints on the scene, and that is the criminal.
Hope this helps :)