It seems the second answer you have provided for this question is the best fit for what the question is specifically asking. Have a great day!
You should always pay attention to the focus of the author what is he trying to say and what two main ideas is he comparing or contrasting in a way.
Huck decides not to tell anybody of Jim's escape because if Jim stayed back, he would have been sold. Huck and Jim are both alienated from the society in a number of ways. Their fates are linked right from the first part of the novel. Freed from the hypocrisy of the society they create a heaven of their own.
