Final answer:
Dementia is an organic mental disease secondary to cerebral disease.
Step-by-step explanation:
The answer to the question is C. Cerebral disease. Dementia is an organic mental disease that is secondary to cerebral disease. It is characterized by a decline in cognitive function, including memory loss, confusion, and difficulty with daily tasks. One common cause of dementia is Alzheimer's disease, which is a type of cerebral disease that affects the brain's ability to function properly. Other cerebral diseases that can lead to dementia include vascular dementia and Lewy body dementia.