<span>Option 1: After the Middle Ages, during the Renaissance, a period in which many inventions changed society.
No. This is not a complete sentence.
Option 2: During the Renaissance, several important inventions changed society after the Middle Ages.
No. This seems to imply that the inventions were created, then had long term effects, which is not the information you are trying to portray.
Option 3: After the Renaissance were the Middle Ages.
No. This does not include all of the necessary information.
Option 4: During the Renaissance, a period after the Middle Ages, several important inventions changed society.
Yes. This sentence is structures correctly and includes all of the correct information.
</span>
I believe it's <span>A. metaphors
</span>
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.