Professor Pholman is lecturing about the reflex arc. He tells his students that in the help coordinate contraction of certain muscles and relaxation of others. Answers: a. motor neurons; peripheral nervous system b. motor neurons; spinal cord c. sensory neurons; peripheral nervous system d. interneurons; spinal cord

a. motor neurons; peripheral nervous system                                            

Explanation:

Motor neurons: It is also referred as "motoneuron" and is described as a neuron whose "cell body" is generally located in the "motor cortex", "spinal cord", and the "brainstem" and its axon or fibers are projected towards an individual's spinal cord and outside his or her spinal cord in order to control glands, muscles, and effector organs directly and indirectly.

Peripheral nervous system: It is considered as including every different nerve in an individual's body that is located outside his or her brain and the spinal cord. The mentioned nerves carry specific information from and to the "central nervous system" and therefore provides various complex "body functions".

the answer to this question is d