Concept:
- During the colonial period, several Indian cities earned nicknames based on their dominant industry, similar to how English industrial cities were nicknamed.
- Ahmedabad grew into a major cotton textile mill hub from the 1860s onward, with dozens of large cotton mills, which is why it earned the nickname 'Manchester of India', after England's own cotton-mill city, Manchester.
- Calcutta was the hub for jute, not cotton, and Bombay, though also a cotton mill city, is more commonly linked with trade and the port rather than this specific nickname.
Step 1: Understand the basis of the nickname.
The nickname compares an Indian city's textile industry to Manchester, England's famous cotton mill town, so we need India's biggest cotton-mill city of that era.
Step 2: Recall which Indian city fits that description.
Ahmedabad built up a huge cluster of cotton textile mills starting in the 1860s and kept that identity through the colonial period.
Step 3: Eliminate the other options.
Calcutta's industrial identity was jute, not cotton, Odisha is not even a single city, and Bombay, while a major mill town too, is not the city carrying this specific historical nickname.
Final Answer: Ahmedabad