|Stated you reported "five" layers but just four are present in the answers, I would say C, at kernel layer.|
Your question however would require a description of the referred model of OS since there is no common theory about how to describe an operating system. My answer is bulit by excluding
A There are drivers not related to File System
B There are drivers not related to I/O
D Drivers are not in charge of me,ory management.
In legacy operating systems however the drivers are part of the I/O subsystem i.e. the BIOS while the Kernel manages processes and memory. In those environments there were no layers so again an exact info about the reference model is needed.