Explanation:

- Correct Answer: Option 2 - Inter-University Centre for Astronomy and Astrophysics (IUCAA)

- The IUCAA is leading the LIGO-India project in collaboration with other Indian institutions and international partners.

- Option 1 - Indian Institute of Science (IISc)

- While a prestigious institution in India, IISc is not leading the LIGO-India project.

- Option 2 - Inter-University Centre for Astronomy and Astrophysics (IUCAA)

- IUCAA is a key partner in setting up LIGO-India, responsible for its coordination and scientific direction.

- Option 3 - Indian Space Research Organisation (ISRO)

- ISRO is not leading this project but may provide technical expertise and support for the project.

- Option 4 - Geological Survey of India (GSI)

- GSI deals with geological surveys and studies, not with astronomy or the LIGO-India initiative.