(1) All persons under nineteen years of age are declared to be minors, but in case any person marries under the age of nineteen years, his or her minority ends.
(2) Upon becoming the age of majority, a person is considered an adult and acquires all rights and responsibilities granted or imposed by statute or common law, except that a person:
(a) Eighteen years of age or older and who is not a ward of the state may:
(i) Enter into a binding contract or lease of whatever kind or nature and shall be legally responsible for such contract or lease, including legal responsibility to third parties;
(ii) Execute, sign, authorize, or otherwise authenticate (A) an effective financing statement, (B) a promissory note or other instrument evidencing an obligation to repay, or (C) a mortgage, trust deed, security agreement, financing statement, or other security instrument to grant a lien or security interest in real or personal property or fixtures, and shall be legally responsible for such document, including legal responsibility to third parties; and
(iii) Acquire or convey title to real property and shall have legal responsibility for such acquisition or conveyance, including legal responsibility to third parties; and
(b) Eighteen years of age or older may consent to mental health services for himself or herself without the consent of his or her parent or guardian.