The MOST likely concern for JKL, Inc. regarding the supplier's increased production rate from 100 to 105 units a month would be B. Deteriorating quality. When production rates increase beyond the standard capacity, there is a risk that the quality of the products may decline as the process may be rushed or overextended1. This is a common concern in supply chain management, as maintaining the quality of products is crucial for customer satisfaction and the company's reputation2.