If a Sponsor is intending to create both an eCTD, and a future paper$-$based CTD for their Rest of the World $($ROW$)$ markets.

Assess the scenario: To meet the requirements of the eCTD Granularity assessment which ICH guideline completely describe the requirements of unique headers and footers to include specific subject matter?

A$.)$ ICH M$4$ Granularity Document

B$.)$ ICH MB

C$.)$ ICH M$2$ Granularity Document