For the purpose of this act the following persons shall be deemed to be engaged in the practice of medicine and surgery:

(a) Persons who publicly profess to be physicians or surgeons, or publicly profess to assume the duties incident to the practice of medicine or surgery or any of their branches.

(b) Persons who prescribe, recommend or furnish medicine or drugs, or perform any surgical operation of whatever nature by the use of any surgical instrument, procedure, equipment or mechanical device for the diagnosis, cure or relief of any wounds, fractures, bodily injury, infirmity, disease, physical or mental illness or psychological disorder, of human beings.

(c) Persons who attach to their name the title M.D., surgeon, physician, physician and surgeon, or any other word or abbreviation indicating that they are engaged in the treatment or diagnosis of ailments, diseases or injuries of human beings.