题目选项分析

A convenience store manager noticed that a cooler which had been stocked with only a cola product and an iced-tea product had 15 colas left at the end of the day but only 3 iced-tea beverages. As a result, the manager reasoned that he should increase the amount of iced tea and decrease the amount of cola he ordered from the distributor.

Which of the following, if true, would most strengthen the manager's rationale for ordering more iced tea and less cola?

【选项】 During that week, a special "buy one, get one free" sale was in effect for the cola beverage.