Given the following scenario, which of the following is the best answer and why?
Tommy was skiing without a helmet, fell and hit his head. He was taken to the hospital.

The doctors decided to perform only an MRI because he had an injury to his head.
The doctors decided to perform only a CT scan because he had an injury to his head.
The doctors decided to perform both a MRI and a CT scan because he had an injury to his head.
The doctors decided not to perform a MRI or a CT scan because he had an injury to his head.