what is the entropy change for the hot reservoir?

Question

Heat flows between two reservoirs having temperatures 1000 K and 500 K, respectively. If the entropy change of the cold reservoir is 10 KJ/K, then what is the entropy change for the hot reservoir?

         (a) – 10 kJ/K                  (b) – 5 kJ/K

         (c) 5 kJ/K                       (d) 10 kJ/K