Final answer:
The Pueblo Revolt of 1680 is an example where Native Americans acted in self-defense to preserve their cultural identity and autonomy against Spanish efforts to assimilate them.
Step-by-step explanation:
An example of Native Americans acting in their own self-interest in relation to European powers is depicted in the Pueblo Revolt of 1680. This event illustrates Native Americans establishing an alliance for mutual defense (option b) against the Spanish, aiming to preserve their cultural identity and autonomy. The Pueblo people's resistance showcases their commitment to maintaining their way of life in the face of external pressures to conform, ultimately revealing the depth of their desire to protect their traditional practices and governance from complete assimilation by the Spanish.