Which is the smallest district of India in terms of geographical area (size)?

Introduction / Context:
This question belongs to Indian political and administrative geography and asks about the smallest district of India by area. District-level facts appear regularly in exams, especially when they represent extremes such as largest or smallest, highest or lowest. Mahe is a small coastal district that often surprises learners because it belongs to the Union Territory of Puducherry but is located geographically within Kerala.

Given Data / Assumptions:
- The parameter considered is geographical area, not population.
- The options include Mahe, Zila, Kaushambi, None of these and Diu.
- We assume the usual district boundaries notified by the Government of India at the time of standard GK references.
- "Zila" is a generic term meaning district, not the name of a specific district.

Concept / Approach:
Mahe is a very small enclave of the Union Territory of Puducherry located on the Malabar Coast surrounded by Kerala. Because of historic French colonial control, Puducherry is made up of several separated enclaves: Puducherry, Karaikal, Yanam and Mahe. Mahe district covers an area of less than 10 square kilometres, making it the smallest district in India by area. Kaushambi is a district in Uttar Pradesh and is much larger. Diu is a district-level unit in the Union Territory of Dadra and Nagar Haveli and Daman and Diu but is still bigger than Mahe.

Step-by-Step Solution:
Step 1: Recall that Mahe is a tiny coastal enclave administered by the Union Territory of Puducherry, located on the Kerala coast.Step 2: Mahe has a very small land area, often cited in GK books as less than 10 square kilometres.Step 3: Compare this with Kaushambi, a full-sized district in Uttar Pradesh with much greater area.Step 4: Understand that "Zila" is not a specific district name; it is the Hindi word for district and therefore cannot be the correct answer.Step 5: Diu is also small but still larger than Mahe when measured in square kilometres.Step 6: Therefore, Mahe is the smallest district of India by area.

Verification / Alternative check:
State and district profile tables in government or exam-oriented publications list Mahe as the smallest district in terms of area. Geography handbooks and competitive exam guides often pair it with Kutch in Gujarat, which is the largest district by area. Looking at a political map of India that marks district boundaries, Mahe appears as a tiny strip along the Kerala coast, confirming its very small geographical size.

Why Other Options Are Wrong:
Zila: This is a generic Hindi term meaning district and not the name of any particular district.
Kaushambi: A district in Uttar Pradesh with a substantially larger area than Mahe.

None of these: Incorrect because a correct specific option (Mahe) is already provided.
Diu: A small district but still not the smallest when compared with Mahe.

Common Pitfalls:
Students sometimes pick Diu because it is widely known as a small coastal district and tourist destination, overlooking Mahe due to its low visibility and enclave status. Another pitfall is ignoring unusual administrative arrangements where a Union Territory like Puducherry can have tiny separated districts. Remembering the pair "Kutch is the largest district, Mahe is the smallest district" is a helpful mnemonic.

Final Answer:
Mahe