Which type of neuron is responsible for signaling another neuron only?

Interneurons are specialized neurons that primarily function to connect other neurons within the same region of the nervous system. They are crucial for processing information received from sensory neurons and communicating that to motor neurons or other interneurons. This makes them integral in reflexes and coordinating complex activities, as they facilitate communication between different types of neurons without directly interacting with the external environment or muscles.

Motor neurons convey signals from the brain and spinal cord to muscles or glands, and sensory neurons transmit information from sensory receptors to the central nervous system. Bi-polar neurons, while a specific type of neuron mainly found in sensory pathways (like vision), do not exclusively signal other neurons. Therefore, the unique role of interneurons in exclusively connecting and signaling other neurons is what makes this option the correct choice.