Quantal analysis shows that a single action potential at the neuromuscular junction causes an EPSP ...

Quantal analysis shows that a single action potential at the neuromuscular junction causes an EPSP of 40 mV or more as against only a few tenths of a millivolt at many CNS synapses. What accounts for this difference? Choose the correct option.
 
  A) A larger number of synaptic vesicles releasing neurotransmitter at the neuromuscular junction compared with CNS synapses
  B) A larger number of transmitter molecules within the synaptic vesicles of a motor neuron compared with CNS synapses
  C) Larger receptors at the neuromuscular junction compared with CNS synapses
  D) A larger synaptic cleft at neuromuscular junction compared with CNS synapses