Answer:
b. Attrition
Explanation:
Based on the information provided within the question this is known as Attrition or Guest Room Attrition. Like mentioned in the question this is the difference between the amount of rooms that were requested and the amount of rooms that were actually used at the end. For example, if you book 20 rooms and your attrition rate is 75% then you must use at least 15 rooms or you will most likely be charged a fine.
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