Explain IN ENGLISH how to form the usted form of the imperative of the regular -ar verb hablar. I know that it is habla but how would one come to this conclusion?

Which one of the following is the correct rhyme to keep in mind when using the spanish counterparts to this, that, those and these? a: “that” and “those” both have s’s, “this” and “these” don’t b: “that” and “those” both have t’s, “this” and “these” don’t c: “this” and “these” both have s’s, “that” and “those” don’t d: “this” and “these” both have t’s, “that” and “those” don’t