Match the items of List I with the items of List II and select the correct answer.

List-I	List-II
a. Coupons	1. Using one brand to advertise another non-competing brand
b. Tie-in promotions	2. Offers to consumers of savings off the regular price of a product
c. Cross promotions	3. Certificates entitling the bearer to a stated saving on the purchase of a specific product
d. Price packs	4. Two or more brands or companies team up on coupons, refunds and contests to increase pulling power