Answer: a. cross-ruffing
Explanation:
Cross-ruffing coupons are coupons that are offered to a person buying a good on another good to encourage them to buy that other good as well. These are usually offered on goods produced by the same company or companies that have a relationship with each other.
They are a brilliant marketing ploy to result in one relating goods to another to boost sales. Offering a coupon on a bag of potato chips upon buying a bottle of Pepsi is there a cross-ruff coupon.