The question pertains to historical efforts to form the separate state of Jharkhand during the 1920s. The primary focus during that time was on uniting tribal areas from multiple states to address socio-economic and cultural issues. In the context of the question, here is the detailed solution:

1. Historical Context: The demand for a separate Jharkhand state emerged from the tribal communities inhabiting the Chotanagpur Plateau and surrounding areas. Their demand focused on a designated administrative region to better address their needs and preserve their cultural heritage.
2. Involved Regions: The areas sought for the creation of Jharkhand were primarily tribal-dominated and stretched over several neighboring states:
   • Bihar
   • Odisha
   • West Bengal
   • Madhya Pradesh
   These regions were chosen based on the significant tribal populations residing there, building a contiguous geographical and cultural entity.
3. Number of Districts: The demand included a total of 14 districts from these states. This correct option (14) was based on aggregating areas with significant tribal concentration from these regions.
4. Conclusion: Among the given options, 14 is the correct answer reflecting the intended regions for forming a separate Jharkhand state during the 1920s.

The above points demonstrate how the demand shaped around these specific regions, focusing on creating a unified administrative body to cater to the tribal populations' needs and aspirations.