Final answer:
Successful price discrimination is not possible in a perfectly competitive market due to the perfectly elastic demand curve faced by firms, which forces them to be price takers rather than price setters. Therefore correct option is B
Step-by-step explanation:
Successful price discrimination cannot take place in a market if the market is perfectly competitive. This is because a perfectly competitive firm faces a perfectly elastic demand curve, meaning that firms are price takers and can sell any number of units at the prevailing market price without having the ability to influence the market price. In contrast, a monopolistic competitor can indeed engage in price discrimination to some degree due to the downward-sloping demand curve it faces, which indicates that raising prices may lead to a loss of some customers, but not all, due to the presence of close substitutes.
Furthermore, markets where segmentation into different buyer groups is possible can facilitate conditions for price discrimination. However, price discrimination is not feasible under perfect competition, where customers can't be segmented and the firm cannot charge different prices to different buyers.