interneurons are for uncontrolable reflixes like when you are about to touch a hot stove and your hand automatically jerks without you consciously thinking about it. Thats because the brain is bypassed in this step. If it weren't you might have gotten burnt.
Sensory neurons are responsible for sensory stimulations i.e. when you sense light it enters your optical system and is processed by sensory neurons
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Myelin sheath is just the covering of some axons of the neurons that makes the transfer of impulses rapid like 100x faster.
YOUR ANSWER IS MOTOR neuron
