USE AN APPROPRIATE REFERENCE TO DESCRIBE THE FUNCTIONAL SIGNIFICANCE OF AN UPPER MOTOR NEURON AND A LOWER MOTOR NEURON 
A. Upper motor neuron: Initiates voluntary muscle movements; Lower motor neuron: Integrates sensory information 
B. Upper motor neuron: Conducts impulses from the spinal cord to muscles; Lower motor neuron: Carries impulses from sensory receptors to the spinal cord 
C. Upper motor neuron: Synapses with lower motor neurons in the spinal cord; Lower motor neuron: Connects the spinal cord to peripheral muscles 
D. Upper motor neuron: Innervates skeletal muscles; Lower motor neuron: Coordinates involuntary reflexes