Answer: E. while beer is homogeneous, the product is differentiated among the sellers.
Explanation: In a bid to construct specific competitive advantages over competitors, sellers of similar or identical products often differentiate them usually through packaging or branding among others. This is known as product differentiation which when successful, leads to competitive advantage. While the beers are identical since they are produced by the same factory, the different stores may differentiate them in order to prod the consumers into choosing one over the other. As a result, Siyed most likely thinks that while the beer is homogeneous, the product is differentiated among the sellers.