Contraction of skeletal muscle fibers is stimulated by what type of neuron?

Motor neuron

Explanation:

A motor neuron is a neuron that is involved in a specialized kind of chemical synapse known as the neuromuscular junction. Within this synapse, the motor neurons terminal axon release the neurotransmitter acetylcholine, which induces muscle contraction via binding of post-synaptic receptors present on the muscle fiber.