Answer : 4. "रबीन्द्रनाथ ठाकुर"
Explanation :

1. Rabindranath Tagore wrote "Amar Sonar Bangla" to inspire the liberation struggle. 

2. The song was written in 1905 during the first partition of Bengal by Lord Curzon. 

3. This song was meant to rekindle the unified spirit of Bengal, to raise public consciousness against the communal political divide. 4. The first ten lines of this song constitute Bangladesh's national anthem, adopted in 1971 during its liberation war. 

5. Rabindranath Tagore was a Nobel laureate for literature and wrote the words and music to India‘s national anthem.