Final answer:
Mexican Americans at the beginning of the 20th century were culturally and linguistically separate from the dominant group, resembling Native American tribes. They faced similar challenges to other marginalized groups, including segregation and systemic racism, but over time built a robust civil rights movement.
Step-by-step explanation:
At the beginning of the 20th century, Mexican Americans were a small group, culturally and linguistically separate from the dominant American society, a situation resembling that of (B) Native American tribes. Like Native American tribes and other ethnic groups such as the Chinese immigrants, Mexican Americans strove to maintain their rights and cultural identity in the face of discrimination and the challenge of living within a society that often relegated them to second-class status. The experiences of Mexican Americans involved dealing with policies that aimed to integrate them into American society yet facing persistent cultural, political, and economic tensions, as seen during the period when American settlers in the Mexican province of Texas, or 'Texans', remained religiously and culturally distinct from the Roman Catholic Tejanos and often clashed with Mexican laws and interests.
In addition, Mexican Americans faced challenges similar to those encountered by other marginalized groups, such as segregation in schools and systemic racism, as well as various socio-economic disadvantages. Nonetheless, over time, the Mexican-American civil rights movement began to grow in strength, demanding improvements in education, employment conditions, and recognition of cultural identity, much like the African-American civil rights movement.