An underlined principle in the marketing of goods is that firms should

The underlined principle in the marketing of goods is that firms should be consumer-oriented. This means that businesses should prioritize understanding and meeting the needs and wants of their target customers. By doing so, they can develop products and services that are tailored to their customers' preferences and market them effectively. This principle also involves building a relationship of trust with customers and ensuring customer satisfaction with the products and services offered. By being consumer-oriented, businesses can establish a strong brand reputation, generate customer loyalty, and ultimately increase sales and profitability.