Option A is the correct model for the expression.
What is wave motion?
'Waves may be graphed as a function of time or distance. A single frequency wave will appear as a sine wave in either case.'
According to the given problem,
Time taken to complete 1 revolution = 4 seconds
The graph A shows that it takes 4 seconds for it to make a full revolution as the length of crest to crest is shown as 4 seconds.
Hence, we can conclude that Graph A is the correct model for the given problem.
Learn more about wave motion here: https://brainly.com/question/26977117
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