The key to a profitable differentiation strategy is

A$)$ to make the nature of the differentiation subjective and hard to quantify and to concentrate on those market segments where buyer repurchase is infrequent.

B$)$ differentiating on the basis of product attributes and features that are not available to a best$-$cost producer.

C$)$

making sure that the differentiating features appeal to sophisticated and prestigious buyers.

D$)$ to keep the costs of differentiating below the price premium that the differentiation approach commands and to incorporate differentiating features that boost unit sales.

E$)$ preventing rivals from imitating the differentiating features by raising buyer switching