There is a difference, which I will address below, which probably tips the scales toward "homemaker" as the better response, BUT as
@spyfy has oft noted, there is not always a specific right answer for a particular item:
Applicants need to use their own best judgment in deciding what is the best, most appropriate, honest and accurate and complete response. There are no fixed formulas or definitive answers for many of the questions.
So either probably is OK.
That said, there is a category of temporary immigration which can lead to permanent residency for an in-home "caregiver," meaning an individual who comes to Canada specifically to be
employed as a care-giver for someone in Canada who needs such care. I do not know if this includes nanny employment or not (I suspect not but I am not well acquainted with this aspect of immigration). In any event, this is different from the care-giver role of a parent or family member.