19.
The answer is: D
Explanation
The correct option is D: 7.
According to the Trade Unions Act, 1926, which was replaced by the Industrial Relations Code, 2020, the minimum number of members required for registration of a trade union is seven. The reason behind this requirement is to encourage the formation of more and more trade unions¹. This ensures that the trade unions have sufficient representation and bargaining power to protect the interests of the workers.