The correct statement regarding a clause is:
- contains both a subject and a verb.
A clause is a grammatical unit that contains a subject and a predicate (verb). It can express a complete thought (independent clause) or may not express a complete thought (dependent clause).
The other statements are incorrect:
- A clause must contain both a subject and a verb; it cannot have only one or the other or be equivalent to a phrase.
- While some clauses can depend on others and may not stand alone as complete sentences (dependent clauses), clauses themselves can stand alone if they are independent.