Final answer:
a. Brand dilution
The scenario with the student's disappointment in the new low-calorie chip is an example of brand dilution, which can negatively affect brand loyalty and hurt the overall brand equity.
Step-by-step explanation:
The problem in branding highlighted by the student's disappointment with the new low-calorie chip, despite liking another product from the same brand, is known as brand dilution. Brand dilution occurs when a brand expands into a market segment or product category that is not congruent with its existing brand image, leading to a decrease in brand equity. In this scenario, the negative experience with the low-calorie chip affected the customer's perception of the mixed-nut bars, even though he previously liked them, potentially reducing his brand loyalty. This contrast with brand extension, which is when a company uses its existing brand name to launch new products in a related category that leverages its existing brand equity, ideally without damaging the brand's reputation or weakening customer trust.