Which Individual Has Presenile Dementia Resulting in Major Neurocognitive Disorder

Which individual has presenile dementia resulting in major neurocognitive disorder?

A) Ellie, who is 43, can't figure out how to turn her stove on, and hasn't been paying her bills because it is too confusing.
B) Jack, who is 43, sometimes feels confused, and takes longer to figure things out, but is still cooking meals and paying bills just fine.
C) Mandy, who is 68, can't use the toilet without assistance any longer, and cannot figure out how to get dressed and undressed.
D) Zachary, who is 93, is sharp as a tack, but feels slower in getting around the house.