System of diarchy remained operational during:

🧠 Explanation:

Dyarchy, implemented from 1921 to 1937 under the 1919 Government of India Act, introduced dual governance in British India. Reserved subjects were controlled by British officials, while transferred subjects were managed by Indian ministers. This limited self-rule aimed to quell demands for independence but faced criticism for its restricted scope. It marked a step toward Indian governance, influencing later reforms. Dyarchy fueled nationalist movements, highlighting the need for full autonomy. Its legacy lies in shaping India’s constitutional evolution and the broader struggle for independence, reflecting the complexities of colonial governance during a transformative period.