Explanation:

All statements are correct.

• The SKAO is not a single telescope but an array of thousands of antennas, to be installed in remote radio-quiet locations in South Africa and Australia, that will operate as one large unit meant to observe and study celestial phenomena. The SKA project is spread across different sites in South Africa and Australia and is headquartered in the United Kingdom.

• India, through the Pune-based National Centre for Radio Astrophysics (NCRA) and some other institutions, has been involved in the development of SKA since its inception in the 1990s.

• Considering the multinational collaboration, SKAO was established as an intergovernmental organisation in 2021 following years of negotiation in which India, too, participated.

• Countries have to sign, and ratify, the SKAO convention to formally become members. The Government’s approval for joining the project, with a financial sanction of Rs 1,250 crore, is the first step towards the ratification.

• India’s main contribution to the SKA is in the development, and operation, of the Telescope Manager element, the “neural network” or the software that will make the telescope work.

Hence option 3rd is correct.