Final answer:
The mylohyoid muscle connects the spine to the chin and plays a role in swallowing, jaw movement, and speech.
Step-by-step explanation:
The muscle that connects the spine to the chin is called the mylohyoid muscle. It is responsible for raising the floor of the mouth during swallowing and elevating the hyoid bone. The mylohyoid muscle helps in the movement of the jaw and tongue, allowing for speech and mastication.