At which of the following locations was India’s first indigenous Optical Inter Satellite Link (OISL) unveiled by Astrogate Labs? 

An agreement has been signed among six states for the Kishau Multipurpose Project, located on which of the following rivers?

On which of the following days is the International Day of Clean Air for blue skies observed every year?

Princess Astrid passed away at the age of 94. Of which country was she a princess?

At which of the following places was the 6th All India Official Language Conference 2026 held?