Of these choices, neuronal communication between the brain and the muscles of the leg is best conceptualized as

Of these choices, neuronal communication between the brain and the muscles of the leg is best conceptualized as electrical and chemical signaling.
The brain sends signals of the electrical and chemical type to reach the leg and move its muscles. Once these signals get to the muscles of the leg, they are moved into motion as a result of the brain "ordering" the leg to move so that a person could get up or get to another place.

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