All MCQs

A memory block can hold many or large parameters, while a register passes the block address.
This avoids being limited by the small number of available argument registers.

Registers provide a direct and efficient way to pass a small number of system-call arguments.
Larger or more numerous arguments are often placed in a memory block instead.

An API presents stable functions and data types while libraries translate requests into platform-specific system calls.
This improves portability and reduces dependence on low-level calling conventions.

A system call is the programmed entry point through which user software requests a kernel service.
The transition is controlled so privileged operations remain protected.

A graphical user interface presents visual controls that users manipulate directly.
The other choices describe internal operating-system mechanisms rather than a user interface.

A command-line interface accepts textual commands entered through a shell or command interpreter.
A graphical interface relies mainly on windows, icons, menus, and pointing actions.

Protection defines and enforces which subjects may access which objects and operations.
Security is broader and includes authentication, attack resistance, confidentiality, integrity, and related defenses.

Accounting tracks resource usage for billing, quotas, auditing, or performance analysis.
The other options solve synchronization, memory, or I/O transfer problems.

Resource allocation assigns limited hardware and software resources among competing processes and users.
This includes processor scheduling, memory allocation, and device allocation decisions.

Error detection identifies hardware and software faults so the system can respond appropriately.
Illegal addresses and device failures are examples of conditions this service monitors.

The communication service supports information exchange between processes locally or across a network.
It may be implemented with message passing, sockets, shared memory, or related mechanisms.

File-system manipulation includes operations on files and directories such as create, open, read, write, and delete.
The other choices concern processor control, virtualization, or interrupt handling.