The question asks about the author of the famous collection of poems titled Gitanjali.

Identifying the Author of Gitanjali

Gitanjali is a highly acclaimed collection of poems. It is one of the most significant works in modern Indian literature.

Let's consider the options provided:

• Rabindranath Tagore
• Taslima Nasrin
• Sunil Gangopadhyay
• Bankim Chandra Chatterjee

The collection of poems Gitanjali was written by the globally renowned Indian poet, philosopher, and writer, Rabindranath Tagore.

Gitanjali (which translates to "Song Offerings") was originally written in Bengali. Rabindranath Tagore himself translated many of the poems into English. The English version of Gitanjali led to him being awarded the Nobel Prize in Literature in 1913, making him the first non-European to receive this honor.

The other authors listed are also notable figures in Bengali and Indian literature, but Gitanjali is specifically the work of Rabindranath Tagore.

• Taslima Nasrin is a Bangladeshi-Swedish writer known for her feminist views.
• Sunil Gangopadhyay was a prominent Indian poet and novelist in Bengali.
• Bankim Chandra Chatterjee was an Indian novelist, poet, and journalist, famous for writing the national song 'Vande Mataram'.

Therefore, the author of the collection of poems Gitanjali is Rabindranath Tagore.