At the neuromuscular junction:

A. To terminate contraction, acetylcholine is broken down by acetylcholinesterase at the muscle cell membrane. B. Opening of muscarinic acetylcholine receptors increases the sodium permeability of the skeletal muscle membrane. C. Action potential propagation to the lower motor neuron triggers the opening of voltage gated Ca2+ channels allowing Ca2+ to flow into the cell and bind to muscle proteins triggering contraction. D. Action potential propagation to the lower motor neuron terminal opens voltage-gated Ca2+ channels triggering exocytosis of vesicles containing glutamate. E. Acetylcholine binding to acetylcholinesterase results in muscle contraction.