dextar wrote:Here isn't the option 2 wrong here because we are comparing Bob Ruth in the first half of the sentence with his salary in the second half.

(emphasis mine)

no, because this isn't a comparison.

comparisons are structures that actually compare two or more things. there are few words that signal genuine comparisons; the most common are 'like', 'unlike', 'as',** 'as ADJECTIVE as', and 'than' (used in constructions like better than, older than, etc.).

option 2 above uses a subordinate clause (although...), but that clause doesn't make a comparison of any kind.

** 'as' used alone, to compare two clauses. this is not meant to refer to 'as' used as part of some larger construction (e.g., 'as well as').