Amain clause that can stand alone or function as a whole sentence is a(n) independent clause relative clause subordinate clause

The answer is indeed an independent clause.

Explanation:

An independent clause is a sentence that contains a subject and predicate. It's called independent because it is able to express a complete thought and stand alone as a sentence.

A subordinate clause, on the other hand, does not express a complete thought. It depends on the main clause to make sense. And a relative clause is not an essential part of the structure. It adds some information to it, but it can be removed from it without affecting the general meaning.

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