What determines the rate at which action potentials are generated at the axon hillock?
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   the rate at which postsynaptic potentials are generated along the dendrites and cell body of a neuron; | 
   
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   the occurrence of excitatory postsynaptic potentials; | 
   
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   the occurrence of inhibitory postsynaptic potentials; | 
   
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   the integration of inhibitory and excitatory postsynaptic potentials at any given moment; | 
   
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   all of the alternatives are correct; | 
   
   
   
   
   
   [Review Part 1 of the tutorial]
   [Review Part 2 (Matching) of the tutorial]