This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
Excitatory post synaptic potential is 
Select and explain. 
A. Depolarisation of post synaptic membrane by opening of K+ channels, B. Hyperpolarisation of post synaptic membrane by opening of Cl- channels, C. Depolarisation of post synaptic membrane by opening of Ca2+ channels, D. Hyperpolarisation of post synaptic membrane by opening of Na+ channel
C: Depolarisation of post synaptic membrane by opening of Ca2+ channels
Answer: C: Depolarisation of post synaptic membrane by opening of Ca2+ channels 
Explanation: EPSP: Depolarisation of post synaptic membrane by opening of Na+ or Ca2+ channels
IPSP : Hyperpolarisation of post synaptic membrane by opening of Cl- or K+ channels