In the paragraph, the words resident and inhabitants are synonyms, words that have the same meaning (in that case it means <em>someone that lives in X place, ) </em>and that can be interchanged when you are writing as a way for not repeating the same word twice.
As for the options, the last phrase contains two synonyms as well, the words shelter and refuge. Both words means <em>a place where one is protected; </em>in that case, protected from the rain and wind.
