Something the firm can persistently do better than its competitors.

Includes customer, operational, product, and/or location excellence, is the right answer.

Explanation:

In marketing, a competitive advantage is a quality that permits industries to beat their contenders. A competitive advantage may involve availability to natural resources, including a low-cost power source or the high-grade ores, geographic location, introduction to modern technology and high entry barriers.

This concept of "Competitive Advantage" is the support a firm has over its contenders. There are various ways to gain this advantage such as by offering greater value to the clients, advertising goods or services with more economical prices etc.