Yes if they lived with you all year, you provided more than half their support and they had less than $4,700 in taxable income.
The person might be your "qualified relative" for whom you will get the $500 credit for other dependents.
CREDIT FOR OTHER DEPENDENTS
what is the household?
If the parent is in a nursing home, is she a member of my household, or of her household?
If the parent still owns a home, unoccupied, is it just the possible rent that would be part of the parent's support? That seems to be what the worksheet says. It also says do not include real estate taxes.
To claim an unrelated relative as a dependent, they must live in your home the entire year, AND have less than $4700 of taxable income, AND you paid more than half their total support.
Remember that even though social security disability is not usually taxable, it counts as support they provide themself. You would need to add up their cost of living (including the value of the home you provided, and any other support, plus their travel, medical, entertainment, and so on); and then determine if you provided more than half of their overall financial needs.