Water with specific heat $$(c_p = 4 kJ/kgK)$$ is fed to a boiler at $$30^\circ C$$, the enthalpy of vaporization at atmospheric pressure in the boiler is 2400 kJ/kg, the steam coming from the boiler is 0.9 dry. The net heat supplied (in kJ/kg) in the boiler is

A

2160

B

2400

C

2440

D

2280