Final answer:
Age and gender have been fundamental market segmentation variables traditionally, especially for American international marketing, but other factors like income and cultural background are gaining importance in segmentation strategies.
Step-by-step explanation:
The question pertains to the use of age and gender as market segmentation variables in international marketing, particularly by Americans. Market segmentation is a marketing strategy that involves dividing a broad target market into subsets of consumers who have common needs and priorities, and then designing and implementing strategies to target them. Age and gender have traditionally been considered the most obvious segmentation variables, as they are easily identifiable characteristics that can influence buying behavior and product preferences. However, it's also important to recognize that other factors, such as income, education, and cultural background, have become increasingly important in market segmentation strategies as the global market becomes more diverse.