Except as provided in subsection (b) of this section, a license holder may not employ an individual under the age of 21 years to sell or deliver alcoholic beverages. A license holder may employ an individual at least 18 years old to: serve and sell alcoholic beverages in a restaurant in connection with the serving or selling of a meal; serve alcoholic beverages from a service bar to a seated customer; or operate a lottery ticket terminal in a premises for which a Class A license has been issued. A license holder may not employ an individual under the age of 18 years to handle alcoholic beverages.