a. Wild celebration
A revel is a wild celebration. Your context clue here is the detail that it went "whirlingly on". This gives the image that things are spinning and it is something that could end at midnight. An party hat doesn't end at midnight. A type of dance is something that can spin, but it usually doesn't continue on until midnight. A specific dance type usually only last for a few minutes. An appearance does not make sense.
Answer:
Aziz would have told us if he had known the answer
1) Accuracy. Verify the information you already know against the information found in the source. Look also for disclaimers as to the accuracy of the content. You may also want to double-check the information against a source that you already know is trustworthy. Even though a source may use technical language, the content may be misleading.
2) Authority. Make sure the source is written by a trustworthy author and/or institution. If you are using a webpage, you can usually identify the owner/publisher by the URL, or check for a copyright statement near the bottom of the page. Make sure the author has the proper credentials on the subject matter. Also, determine if the source is biased. For example, if it is medical information from a drug company, that company will provide information in support of its product. Be aware of the objectivity of the author and his/her viewpoints.
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The Deerslayer, The Last of the Mohicans, The Pathfinder, The Pioneers, and The Prairie.