Correct Answer: (a) Jantar Mantar, Delhi
Solution:In the early 18th century, Maharaja Jai Singh II of Jaipur constructed five Jantar Mantars in total, in- New Delhi,
- Jaipur,
- Ujjain,
- Mathura
- and Varansi;
they were completed between 1724 and 1735.
There are 13 astronomical instruments at Delhi's Jantar Mantar.
Here are the main and famous ones: