What is the purpose of a miscellaneous charges order (MCO) in travel services?

A miscellaneous charges order (MCO) is specifically used in travel services to document charges when standard ticket stock cannot be utilized. This could happen in various scenarios, such as when additional services are provided, like excess baggage fees or travel-related charges that don't fall under the typical ticketing parameters. MCOs allow travel agents to ensure that all charges are properly recorded and accounted for, even when traditional ticketing methods aren't applicable. This makes option C the most accurate answer, highlighting the MCO's role in maintaining proper financial records in the travel industry.