Answer:B early signs of dementia, probably Alzheimer's disease.
Explanation:Her being in her 70's makes it very likely to be affected by dementia.
Disorientation is also one of the signs of this disorder or disease.
She also did not recognize her husband which is also a sign because one will start to forget faces of people they have known for years.
She can't recall the recent information such as the fact that they have discussed the next morning plans but she had forgotten.