Answer:
a.trade shows
Step-by-step explanation:
Trade shows provide for the advertisement which is for the specific industry performers, it do not target the entire audience rather some specific users who shall be interested. It is the best advertisement related to the products which are specific to some industries.
Here, the product that is long lasting breath mints is basically for the people who use tobacco, or smokes. So it is based on for stores which are specific in selling these products. Accordingly rather than using any other method of advertisement to address various store managers of the same industry, Trade shows will be the best chosen technique.