The correct answer is option 1: Non-cooperation, civil disobedience, and boycott.
Non-cooperation is a form of Satyagraha in which individuals refuse to cooperate with an unjust system or government. It involves withdrawal of support and engagement, such as boycotting institutions and products.
Civil disobedience involves the intentional violation of unjust laws as a means to bring attention to the injustice and provoke a change in the system. This can include acts like peaceful protests, sit-ins, and acts of defiance.
Boycott is another form of Satyagraha wherein individuals and communities refuse to purchase, support or engage with products, services, or institutions associated with injustice. It is an effective way to show economic and social resistance against oppressive systems.
Option 2, Rebellion, is not a form of Satyagraha as it implies a violent uprising against an unjust system.
Option 3, Revolution and referendum, are forms of political action but not specific to Satyagraha.
Option 4, Plebiscite, is a method of voting but not a form of Satyagraha.
Overall, the three important forms of Satyagraha are non-cooperation, civil disobedience, and boycott.