A Researcher Constructed a Reaction Vessel and Connected It to a Spectrophotometer

A researcher constructed a reaction vessel and connected it to a spectrophotometer so that the concentrations of all species in the vessel could be measured simultaneously. At 25°C all of the concentrations were measured and the equilibrium constant (K_c) was calculated to be 3445. The temperature was increased to 75°C, the concentrations measured, and the equilibrium constant calculated to be 9015. What is the DH_rxn?

A) -45.1 kJ
B) 45.1 kJ
C) -16.6 kJ
D) -7.2 kJ
E) None of the above