Explanation:

- Gram Sabha: These are grassroots democratic bodies in Indian villages. They are part of the Panchayati Raj system but are not referred to as the 'popular chamber.'

- Rajya Sabha: This is the upper house of India's Parliament, akin to the Senate in other countries. It's not considered the 'popular chamber' as members are elected by state legislatures.

- State Assembly: These are legislative bodies at the state level. While important, they are not termed as the 'popular chamber' at the national level.

- Lok Sabha: The lower house of India's Parliament. Known as the 'popular chamber' as its members are directly elected by the citizens, making it representative of the public's voice.