Final answer:
The force responsible for holding a yo-yo in a circular path is tension.
Step-by-step explanation:
The force responsible for holding a yo-yo swung on a string in a circular path is Tension.
When a yo-yo is swung, the string exerts a force on the yo-yo, pulling it towards the center of the circular path. This force is called tension. Tension is responsible for providing the necessary centripetal force that keeps the yo-yo moving in a circular path. Without tension, the yo-yo would move in a straight line rather than a circular path.