Any one or any combination of the following practices shall constitute the practice of optometry:
(1) The examination of the human eye by any method, other than surgery, to diagnose, to treat, or to refer for consultation or treatment any abnormal condition of the human eye and its adnexa; or
(2) The employment of instruments, devices, pharmaceutical agents and procedures, other than surgery, intended for the purposes of investigating, examining, treating, diagnosing or correcting visual defects or abnormal conditions of the human eye or its adnexa; or
(3) The prescribing and application of lenses, devices containing lenses, prisms, contact lenses, orthoptics, vision training, pharmaceutical agents, and prosthetic devices to correct, relieve, or treat defects or abnormal conditions of the human eye or its adnexa.