How many electrons must be transferred to a body to produce a charge of 125 nc?

given:
   charge to be produced =125 nc or 125*10^-9 c.
   to find:
   Number of electrons required to produce a charge of 125 nc.
   solution:
    the charge of an electron is 1.602 x 10^-19 C:
    Then, number of electrons = 125 x 10^-9 / (1.602 x 10^-19)
  = 78 x 10 ^ 10 electrons
  so, 78 x 10^10 electrons must be transferred to a body to produce a charge of 125nc.

The correct answer is  "c".  it is "c" because melting is an endothermic change, and endothermic get's energy from surroundings.