In the San Francisco market, Kellogg's Raisin Bran sells for $3.49 per box, and Post Raisin Bran sells for $3.39 per box. Both Kellogg's and Post promote their cereals with weekly coupons in the local newspaper. Kellogg's and Post are most likely engaged in A. exclusive distribution B. intra-brand price competition C. vertical integration D. inter-brand price competition E. dual distribution competition