After an injury, a person notices he or she has become much more clumsy, occasionally stumbling and falling. Which part of the brain was most likely to have been injured?

The cerebellum helps coordinate movement and maintain balance. Injury to it can cause clumsiness, stumbling, and falls, so the most likely injured part is the cerebellum. The cerebrum is more involved in functions such as thought and voluntary actions, while the brainstem controls basic functions such as breathing and heart rate.

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