Which sentence is an independent clause?

i would suggest the red, white, and blue shoes; they are perfect for the fourth of july celebration.

if you are attending the fourth of july celebration, i suggest you wear the red, white, and blue shoes.

if you are attending the fourth of july celebration, i suggest you wear the red, white, and blue shoes; you will definitely win the contest.

the red, white, and blue shoes are perfect for the fourth of july celebration.

The answer is D:  An independent clause is a sentence considered grammaticaly complete, it contains enough information to be able to stand alone. It contains a subject and a verb, so the readers can know who the sentence talks about and what action is performed. "The red, white, and blue shoes (subject) are (verb) perfect for the fourth of July celebration.  

The answer is indeed letter D) The red, white, and blue shoes are perfect for the Fourth of July celebration.

Explanation:

We were asked to find the sentence that is an independent clause. An independent clause has a subject and a predicate. It expresses a complete thought on its own. The sentence in letter D has those characteristics. It is perfectly understandable on its own, meaning it expresses a complete thought. It has a subject - "The red, white, and blue shoes" - and a predicate - "are perfect for the Fourth of July celebration."

Letter A is a sentence composed of two independent clauses connected by a semicolon. Letter B is a conditional clause, which means the clause with "if" is subordinate (dependent) to the main clause. Letter C has a conditional clause and two independent clauses. Thus, the one that best answers the question is letter D, since the whole sentence is an independent clause.

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