Customer loyalty is best defined as:

Customer loyalty is best defined as a commitment to repurchase from a brand. This concept emphasizes a customer's long-term dedication to a specific brand or company, which is driven by positive experiences, satisfaction, and trust built over time. Loyal customers are less likely to switch to competitors and are more inclined to continue purchasing from the same brand, even in the presence of alternatives.

This commitment usually results from the perceived value a customer receives, whether through product quality, customer service, or overall brand engagement. When customers feel valued and have positive interactions with a brand, they develop a bond that encourages repeat business.

The other choices, while relevant to consumer behavior, do not encapsulate the essence of customer loyalty. Trying multiple brands does not signify loyalty; instead, it indicates exploration or a lack of preference. Random buying behavior implies inconsistency and a lack of commitment, while only purchasing when discounts are available suggests a transactional relationship rather than a loyal one. These behaviors do not reflect the deeper commitment associated with true customer loyalty.