Final answer:
The sentence punctuated correctly is: I will tell you one more time: do not touch my computer again.
Step-by-step explanation:
The sentence punctuated correctly is: I will tell you one more time: do not touch my computer again.
In this sentence, the colon is used correctly to introduce the direct speech. The words before the colon form a complete sentence, and the words after the colon are capitalized because they are the beginning of a direct quotation.
The other two sentences have incorrect punctuation. In the first sentence, the quotation marks should be placed outside the apostrophe to indicate possession: The movie Bambi is my nephew 'Carson's' favorite movie. In the second sentence, the capitalization after the colon is unnecessary because it does not start a direct quotation: Lydia's family is going to Austin Texas for the Rodriguez family reunion.
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