Final answer:
A clearly defined mission helps management evaluate available market opportunities and avoid those that are inconsistent.
Step-by-step explanation:
The major advantage of having a clearly defined mission is B. A clearly defined mission helps management evaluate available market opportunities and avoid those that are inconsistent. When a company has a clear mission statement, it serves as a guiding principle for decision-making. It helps management assess potential market opportunities and determine which ones align with the company's mission and objectives. This prevents the company from pursuing opportunities that are not in line with its mission, saving resources and ensuring a focused approach.