Which is a correctly punctuated compound sentence?

A compound sentence is a sentence that has two independent clauses joined by a coordinating conjunction (and, nor, but, or), a conjunctive adverb (therefore, etc.) or a semicolon alone (;). For example: Mary is watching TV but Sam is playing thhe piano. John cooks great however Sara cooks even better.

this question is not school related. refrain from asking non school or academic related questions in the future.