Person 76 very independent but always asks me I'm daughter be very patient lives dad very active man thank god.
On this site, there is an explanation of the stages here: https://www.agingcare.com/articles/Stages-of-Alzheimers-disease-118964.htm
That one observation -- not recognizing a particular object -- may not be enough to determine stage. Also, be aware that the stages apply to ALZ but not other kinds of dementia.