The value indicated by Fermi-energy level in an intrinsic semiconductor is 
 

• Where n is the number of electrons and p is the number of holes in an intrinsic semiconductor, n=p.
• This indicates that the likelihood of discovering an electron at the conduction band edge and equal no. of holes at the valence band edge.
• As a result, in intrinsic semiconductors, the average energy level of electrons and holes is equal to half of the energy band gap. 
• Additionally, in intrinsic semiconductors, the Fermi energy level is located precisely at the centre of the energy band gap.
• Thus, the average energy of electrons and holes is the value given by the Fermi energy level in an intrinsic semiconductor.

Hence the correct answer is The average energy of electrons and holes .