Final answer:
Nationalism can lead to discrimination via the exclusion of those not sharing the dominant traits of the nation's identity, such as language or culture. This negative aspect of nationalism can foster superiority complexes and social exclusion, as seen historically in countries like 19th-century Germany and in the Balkans.
Step-by-step explanation:
Nationalism, rising significantly during the 19th century, can be understood as a sense of pride and loyalty towards one's nation, often emphasizing a common ancestry, language, or culture. The adverse effects of such a strong sense of nationalism can lead to discrimination against those who do not share the dominant cultural traits within a region. This is because one of the darker sides of nationalism is the potential to exclude or marginalize individuals or groups that do not conform to the dominant nationality's characteristics, such as background, language, or culture. Therefore, the correct answer to how nationalism could be used to discriminate within a region would be (b) by excluding those who don't share the dominant background, language, or culture.
Historically, nationalism has supported and justified the drive for nations to form based on shared characteristics, leading to a sense of unity and self-determination for many people. However, this same drive can foster a sense that the nation's culture is superior to others, sometimes contributing to social exclusion, repression of minority groups, and violent conflicts. Countries like Germany during the 19th and 20th centuries and others within the Balkan region displayed such nationalistic tendencies, with differing definitions and consequences.