What is a neural pathway that detects a stimulus and generates a rapid response without conscious thought?

The correct answer is the reflex arc.

A neural pathway that detects a stimulus and generates a rapid response without conscious thought defines a reflex arc. It is a rapid and automatic response to a stimulus that occurs without conscious thought or input from the brain. The reflex arc includes sensory neurons, interneurons, and motor neurons that work together to produce a reflex action. These actions can occur in response to various stimuli, including pain, heat, and touch, and are important for protecting the body from potential harm.