A user program executes in a , in which certain areas of memory are protected from the user's use, and in which certain instructions may not be executed.

User Mode

Explanation:

Programs Can be Executed in two modes namely:

User Mode

In User mode, the executing program has no ability to directly access hardware or reference memory. Program running in user mode must delegate to system APIs to access hardware or memory. Due to the protection afforded by this sort of isolation, crashes in user mode are always recoverable. Most of the program running on your computer will execute in user mode.

Kernel Mode

In Kernel mode, the executing program has complete and unrestricted access to the underlying hardware. It can execute any CPU instruction and reference any memory address. Kernel mode is generally reserved for the lowest-level, most trusted functions of the operating system. Crashes in kernel mode are catastrophic; they will halt the entire PC.

answer; i believe the correct answer is (a) all trenches must have access/egress;