It could be settlers or diseases, more likely diseases
Answer:
After a three-month siege, Spanish forces under Hernán Cortés capture Tenochtitlán, the capital of the Aztec empire. Cortés' men leveled the city and captured Cuauhtémoc, the Aztec emperor. So the downfall was mostly on the Spanish.
Explanation:
The correct answer is C, their limited feelings of responsibility. Social psychologists John Darley and Bibb Latane have introduced the concept of the bystander effect. This is a term describing how the presence of others can discourage someone from intervening in an emergency. It is based on the sociopsychological phenomenon of the diffusion of responsibility and how a person is less likely to take responsibility for an action or inaction when others are present. This leads to the individual transferring the responsibility of acting on the rest of the group.