【单选题】Prom/Promotion price refers to ( ).
A.
a product, service, or programme that is offered at reduced prices or rates.
B.
a product, service or programme that is offered at a 30% discount to consumers.
C.
a product or service that is offered at a lower price than regular price during the promotion.
D.
a product or service that is offered to consumers at a regular price while the second one is offered to them for free.