Which command is used to compare two possible words or character sets that match?

The command used to compare two possible words or character sets that match is grep. This utility is designed specifically for searching text using patterns defined by regular expressions. When using grep, you can provide a string or pattern to search for within a file or input stream, and it will return lines that contain matches to that pattern.

Grep supports various options for pattern matching, including the use of wildcards and character sets, allowing users to refine their searches based on specific criteria. For example, you can use brackets to specify a range of characters or a set of characters to search for. This functionality makes grep an essential tool for comparing and filtering through text data based on matching words or character patterns.

The other commands listed serve different purposes. Cat is primarily used for concatenating and displaying file contents, sort is used for sorting lines of text files, and wc (word count) is used for counting lines, words, and characters in text. While these commands are useful for various tasks in Linux, they do not provide the specific functionality to compare words or character sets in the way that grep does.