India's first underground nuclear test site: identify the location where the first underground test was conducted.

Introduction / Context:
Understanding milestone events in a nation’s nuclear history is common general knowledge for engineering and GK exams. India’s first underground nuclear test is a frequently asked factoid tied to geography and strategic programmes.

Given Data / Assumptions:

• The question asks for the specific site of the first underground test.
• We are identifying the location by name.

Concept / Approach:
India’s inaugural underground nuclear test was conducted at the Pokhran Test Range in Rajasthan. The site is distinct from nearby cities or nuclear power stations and is a purpose-built range in the Thar Desert region.

Step-by-Step Solution:
Recall the well-known test range name associated with India’s early nuclear tests.Distinguish it from other nuclear locations like Kalpakkam (power/fast-breeder programmes) or Narora (power station).Select Pokhran as the correct site.

Verification / Alternative check:
Historical references widely identify Pokhran as the test site for the first underground detonation, with subsequent tests also associated with the Pokhran range.

Why Other Options Are Wrong:
Jaisalmer: a district/city in Rajasthan, not the specific test range.Kalpakkam: a nuclear power and research site in Tamil Nadu, not the test range.Narora: a nuclear power station in Uttar Pradesh, not the test site.

Common Pitfalls:
Confusing administrative districts with the dedicated range; selecting a nuclear power location instead of the weapons test range.

Final Answer:
Pokhran