The correct answer is A. All flags were flying.
Explanation
A complete phrase is composed of a subject, a verb, and a compliment that also expresses a completely coherent idea. According to this definition, the correct answer is A. because it has a subject "All flags", a verb "were" and a complement "flying". Also, it expresses a complete and coherent idea.
"<span>This paragraph does not contain a thesis" is the correct answer. A thesis is a stated opinion about a topic, and this is just simply naming facts and occurrences. </span>
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B because it makes sense a than all the other answer choices