Both Bama and Zitkala were individuals who shared several common experiences and struggles, which can be summarized in the statement "all of these." Let us delve into each option to understand why it is correct.

a) Belonged to minority:
Both Bama and Zitkala belonged to minority groups in their respective societies. Bama, a Tamil Dalit woman, faced discrimination and social marginalization due to her caste. Zitkala, a Native American woman, encountered racism and prejudice as a member of the Sioux tribe. Their experiences as minorities influenced their lives and shaped their perspectives.

b) Victims of cultural differences:
Both Bama and Zitkala were victims of cultural differences. Bama, in her autobiography "Karukku," recounts her struggles as a Dalit woman trying to navigate the dominant caste society's expectations and prejudices. Zitkala, in her memoir "American Indian Stories," describes the challenges she faced as a Native American woman assimilating into white American culture at the Carlisle Indian Industrial School. They both experienced conflicts between their own cultural backgrounds and the mainstream society they were a part of.

c) Were struggling because of class:
While the question does not provide specific details about their class struggles, it is evident that both Bama and Zitkala faced socioeconomic challenges. Bama, coming from a marginalized Dalit background, had limited access to educational and employment opportunities. Zitkala, growing up on a reservation, faced poverty and limited resources. Their class positions influenced their experiences and the obstacles they had to overcome.

d) All of these:
Given the explanations above, it is clear that all the options mentioned – belonging to a minority, being victims of cultural differences, and struggling due to class – apply to both Bama and Zitkala. These shared experiences and challenges make option "d" the correct answer.

In conclusion, Bama and Zitkala, despite their different cultural backgrounds and contexts, shared commonalities in terms of belonging to a minority, being victims of cultural differences, and facing struggles related to class. These shared experiences shaped their identities and had a significant impact on their lives.