Which option correctly uses commas to set off a nonrestrictive clause?
A. Plato who was, a Greek philosopher, wrote the tragic story of the
ancient civilization Atlantis.
B. Plato who was a Greek philosopher, wrote the tragic story of the
ancient civilization Atlantis.
C. Plato, who was a Greek philosopher, wrote the tragic story of the
ancient civilization Atlantis.
D. Plato who was a Greek philosopher wrote the tragic story of the
ancient civilization, Atlantis.