The piece of evidence which supports the idea that vacation improves familial relationships is:
According to the given question, we are asked to show evidence that supports the idea that vacations helps to improve family relationships.
As a result of this, we can see that there is an evidence about a sense of calm which is gotten when one spends time away from work and reduces stress which heals the body
Therefore, the correct answer is option C
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https://brainly.com/question/22109106