Final answer:
The correct sentence is: The green paint is a horrible color. I don't want it on my walls.
Step-by-step explanation:
The correct sentence is: The green paint is a horrible color. I don't want it on my walls. The sentence is punctuated correctly because it uses a period (.) to end the first independent clause and starts the second independent clause with a capital letter. This follows the standard rules of punctuation for separating two complete thoughts.
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