Identify the location of India’s first crude oil refinery, referring to early petroleum history and the birthplace of refining operations within the country.

Introduction:
India’s petroleum history begins in Assam, where commercial oil production and refining first took root. This question tests factual recall of that first refinery’s location.

Given Data / Assumptions:

• We are asked for the first crude oil refinery in India.
• Options include several Indian locations.

Concept / Approach:
Use historical knowledge of Indian oil industry milestones. The earliest commercial activities and refining in India were centered in Assam in the late 19th/early 20th century.

Step-by-Step Solution:

Verification / Alternative check:
Industry histories and standard petroleum textbooks cite Digboi (Assam) as India’s first refinery town.

Why Other Options Are Wrong:

Common Pitfalls:
Confusing oilfields with refinery sites, or mixing up later coastal refineries with the first historical one.

Final Answer:
Digboi