Final answer:
Understanding diversity in an international marketing firm means recognizing differences in people's social, cultural, and economic backgrounds. This involves being aware of varying cultural norms, values, and communication styles, and fostering an inclusive work environment.
Step-by-step explanation:
The ability to recognize important differences in people's social, cultural, and economic backgrounds is essential for an HR manager like Mary who deals with the diversity of the company's customers and employees. Understanding this diversity means being aware of the varying cultural norms, values, and communication styles of individuals from different backgrounds. For example, when different cultures interact, misunderstandings may occur due to different expectations or approaches to work. Mary can enhance her understanding of diversity through diversity training and by fostering an inclusive and respectful work environment.