The only one that would really make sense and fit with the marketing concept philosophy would be the first one: we don’t have a marketing department; we have a customer department. For those not in the know on this philosophy, the idea is that you study the customers and what they’re buying. Then, you fit your marketing to fit that and make the product fit the mold so that the marketing will work. This can be a fickle way to market. Each new generation will have different things they value in marketing and what they buy.
The current generation of 20 to 30 year olds prefer to have cheap but good products. Teens prefer trendy, eco-friendly products. The target audience makes all the difference here.