For purposes of this chapter, the following persons are incapacitated persons:
(1) Persons under age eighteen (18) whose disabilities have not been removed;
(2) Persons who are detained or confined by a foreign power or who have disappeared; and
(3) Persons under age twenty-one (21) who:
(A) Have reached eighteen (18) years of age;
(B) Have a current guardianship established based solely on the minority age of the person;
(C) Agree to allow the current guardianship to continue up to twenty-one (21) years of age; and
(D) Receive a guardianship subsidy paid for or approved by the Department of Human Services.