One reversible heat engine operates between $$1600^\circ$$K and $$T_{2}^\circ$$K and another reversible heat engine operates between $$T_{2}^\circ$$K and $$400^\circ$$K. If both the engines have the same heat input and output, then temperature $$T_{2}^\circ$$ is equal to

A

800 K

B

1600 K

C

1200 K

D

6400 K