Is this for K12 Us history? Im gonna answer this in a min
There is no constitutional right to sell an Organ.
Even though constitution admit that you had the full right for full freedom to do whatever you want to your body, selling an organ is strictly illegal because it may create a market that could endanger many of human's life if it's left handled by the private sectors who constantly seek ways to cut expenses.
Well it kinda depends on where you gear your essay to.. few tips:
don't start with a question
if you want start with a fact
make it interesting (catching/hook)
Answer: In this example, the ice cream is the REWARD for Positive REINFORCEMENT.
Explanation: In Psychology, reinforcement can be defined as the process whereby a behavior with desirable consequences comes to be repeated. Reinforcement is applied to promote or encourage a behavior in the future.