Final answer:
The correct temperature for the detergent wash water in the three-sink manual warewashing process is 110°F or higher.
Step-by-step explanation:
In the three-sink manual warewashing process, it's essential that the water temperature in the wash sink is hot enough to remove food and grease effectively, but not so hot that it could cause harm to users or not maintain correct sanitization levels. The correct temperature for the detergent wash water should be at least 110°F or higher to ensure proper cleaning and sanitation. Therefore, the answer to the student's question is a. 110°F or higher.