The event most likely influenced the author's decision to write the letter include option A: The author learned the rules of the art contest.
What is author's decision to write the letter?
The author was disappointed when he/she learned that only adults are able to participate (a rule) in the art contest.
The term is usually associated with art in which the traditions of the past have been thrown aside in a spirit of experimentation.
Therefore, correct option is A.
Learn more about art contest, refer to the link:
https://brainly.com/question/170543
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