Among Aizawl, Agartala, Shillong and Darjeeling, identify the odd place based on whether it is a state capital or not.

Introduction / Context:
This odd one out question comes from basic Indian geography and general knowledge. Competitive exams often test whether the learner can quickly recognize state capitals and distinguish them from other important but non capital cities or hill stations. Here we are given four well known places from the northeastern part of India and asked to pick the one that does not belong with the others when we classify them as state capitals versus non capitals.

Given Data / Assumptions:
The four places given are Aizawl, Agartala, Shillong and Darjeeling. All four are cities or hill stations located in or near the northeastern region of India. We use standard and widely accepted information about Indian state capitals. We assume that the intended classification is based on which places are state capitals and which are not.

Concept / Approach:
The concept is simple classification by administrative status. Some cities are designated as state capitals and host the main offices of the state government, while others may still be famous but do not have capital status. In this question, three of the places are capitals of northeastern states of India, while one place is a famous hill station that does not serve as the capital of any state. The non capital city is therefore the odd one out in this set.

Step-by-Step Solution:
Step 1: Aizawl is the capital city of the state of Mizoram in northeastern India. Step 2: Agartala is the capital city of the state of Tripura, also located in the northeastern region. Step 3: Shillong is the capital city of the state of Meghalaya and is a well known hill station as well. Step 4: Darjeeling, although very famous for its tea gardens and cool climate, is a hill station in West Bengal and not the capital city of any Indian state. The capital of West Bengal is Kolkata. Step 5: Therefore, Aizawl, Agartala and Shillong form a group of state capitals, while Darjeeling does not share this property.

Verification / Alternative check:
A quick verification can be done by recalling or checking a standard list of Indian state capitals where Mizoram, Tripura and Meghalaya clearly list Aizawl, Agartala and Shillong as their capitals respectively. When looking at West Bengal, Darjeeling appears as a tourist town and hill station, while Kolkata is shown as the capital city. Since the administrative role of each city is well defined and does not change frequently, this classification is reliable for exam purposes.

Why Other Options Are Wrong:
Aizawl is not the odd one out because it is a state capital, just like Agartala and Shillong. Agartala is also not the odd one out since it is the capital of Tripura and clearly belongs to the same group of capitals. Shillong is not the odd one out because it is the capital city of Meghalaya and fits with the other capitals. Darjeeling differs from these three because it is not a state capital but a famous hill station in West Bengal.

Common Pitfalls:
Learners sometimes get distracted by the fact that Darjeeling is extremely famous, and might assume it has capital status simply because of its popularity. Another mistake is to focus only on climate or tourism and forget that the question is about administrative importance. To avoid such errors, it helps to remember at least the basic list of Indian state capitals, especially for important states in the northeast region.

Final Answer:
The place that is not a state capital and is therefore the odd one out is Darjeeling.