Final answer:
The equilibrium constant for the reaction cannot be determined from the given information.
Step-by-step explanation:
The equilibrium constant for the reaction between sulfur dioxide and oxygen to produce sulfur trioxide can be determined using the given Kc value of 53.
However, the equilibrium constant for this specific reaction at 550°C cannot be directly determined from the given information.
Therefore, the answer is D) The equilibrium constant cannot be determined from the given information.