"The following persons must wear protective headgear :
"A. If under 15 years of age, a passenger on a motorcycle, motor-driven cycle or
an attached side car;
"B. If under 15 years of age, an operator of an off-road motorcycle or motor-driven
cycle;
"C. An operator of a motorcycle or motor-driven cycle, operating under a learner's
permit or within one year of successfully completing a driving test; and
"D. A passenger of an operator required to wear headgear."