Answer:
B. Dementia.
Step-by-step explanation:
Dementia encompassed a large category of brain diseases. They all have in common that they decrease the ability to think and remember. What types of diseases are the ones that could cause a person´s personality to change. The other options affect the ability to remember important information but they have not the characteristic of changing personality.
One of the most common types of dementia and the one that probably Claretta has is Alzheimer´s disease.
I hope this answer helps you.