The correct answer is D. All of the above.
Paging software is a type of memory management system that divides physical memory into fixed-size pages. Each page can be mapped to a different virtual address, which allows the operating system to manage multiple programs in memory at the same time. Paging software also provides protection mechanisms to prevent programs from accessing each other’s memory.
Option A is correct because paging software implements the access environment for all programs in the system. This includes providing each program with a private address space, managing the mapping between virtual and physical addresses, and enforcing access permissions.
Option B is correct because paging software manages the physical address space. This includes allocating pages of memory to programs, tracking which pages are in use and which are free, and swapping pages between memory and disk.
Option C is correct because paging software provides sharing and protection mechanisms. This allows multiple programs to share data and resources, while also preventing them from accessing each other’s data or resources without permission.
Option E is incorrect because paging software does perform all of the functions listed in the question.