An auto accident rendered chris's nervous system unable to send messages for him to swallow, so he is using a feeding tube. which brain structure was most likely damaged in the accident?

So they are actually three main parts of the brain namely the cerebrum the cerebellum and the medulla oblongata the medulla oblongata should be the answer

The medulla

Explanation:

The medulla is a structure located in the brainstem which lies inferior to the cerebellum and is mainly responsible for controlling the involuntary actions of the body. The various centers that are located in the medulla are - the respiratory center, cardiovascular center, vasomotor center, and reflex center.Out of all the centers, it is the reflex center that is responsible for controlling actions like coughing, sneezing, swallowing, etc. Since in the given question, after the auto accident Chris is unable to  swallow, this shows that there is an injury to the medulla because this is where the reflex center lies.