Final answer:
ISO 9001:2015 certification contributes to increased profitability, reduced cost of production, and improved marketing, which are all internal benefits that enhance business operations and performance.
Step-by-step explanation:
The internal benefits of ISO 9001:2015 certification are multifaceted and can impact various aspects of a business. Answering the student's question, the correct option would be d. all of the above, as ISO 9001:2015 certification can lead to increased profitability, reduction in the cost of producing a product, and improvement in marketing.
Increased profitability can arise from improved operational efficiencies and customer satisfaction, reduced production costs can result from the optimization of processes, and an improvement in marketing efforts can occur due to the enhanced reputation that the certification provides. Overall, ISO 9001:2015 encourages a business to streamline processes, reduce waste, and improve quality, which collectively contribute to these internal benefits.