The correct answer is option 'D', which means that all of the above categories were part of the gigantic merchants guilds of the Chola country. Let's understand each category in detail:

1. Valanjiyar:
The Valanjiyars were a prominent merchant group in the Chola country. They were involved in long-distance trade, particularly in the export and import of goods. The Valanjiyars played a significant role in promoting trade and commerce within the Chola empire and beyond.

2. Nanadesis:
The Nanadesis were another category of merchants guilds in the Chola country. They were involved in local trade and commerce, focusing on regional markets and exchanges. The Nanadesis played a crucial role in the distribution and sale of goods within the Chola empire.

3. Manigramam:
The Manigramam was yet another important category of merchants guilds in the Chola country. They were primarily involved in banking and money-lending activities. The Manigramam merchants were known for their expertise in financial matters and played a vital role in facilitating trade and economic transactions.

Importance of Merchants Guilds:
The merchants guilds of the Chola country were crucial for the economic growth and prosperity of the empire. They played a significant role in promoting trade, both within the empire and with other regions. The guilds facilitated the exchange of goods, ensured the availability of essential commodities, and contributed to the overall development of the Chola economy.

The merchants guilds also played a vital role in the social and cultural fabric of the Chola society. They were involved in philanthropic activities, such as building temples, supporting educational institutions, and contributing to the welfare of the community. The guilds also provided a platform for merchants to come together, share information, and resolve commercial disputes.

Conclusion:
In conclusion, the gigantic merchants guilds of the Chola country included the Valanjiyar, Nanadesis, and Manigramam. Each category of guilds had its own specific role in trade and commerce, contributing to the economic development and social fabric of the Chola empire.