Which of the following is not a system software?

Concept

Software is broadly classified into two families. System software runs and manages the computer itself: it controls hardware resources and provides the platform on which other programs run (e.g., operating systems, device drivers, utility programs, and language translators). Application software, by contrast, is built for an end user to perform a specific real-world task and runs on top of the system software.

Applying it here

The task is to find the one option that does NOT belong to the system-software family. Test each option against the rule above:

• Programming language translators (compilers, interpreters, assemblers) convert source code into machine-executable form so programs can run — a service to the system, hence system software.

• Utility programs (disk cleanup, antivirus, backup, defragmenters) maintain and manage the computer system itself — system software.

• Operating system controls hardware and provides the platform for every other program — the definitive example of system software.

• Database software is used by an end user to store, query and manage their own data for a specific purpose — it serves the user's task, not the running of the machine.

Result

Database software fits the definition of application software, not system software, so it is the odd one out. The other three are all standard system software.

A note on the DBMS nuance

It is true that a DBMS sits close to the system layer — it manages storage, concurrency and access, and some texts describe enterprise DBMS engines as 'system-level' middleware. But standard exam classification, and the comparison demanded here, treats end-user database software as application software because it exists to serve a user's data task. Against the other three options — all unambiguous system software — database software remains the only one that does not belong to the system-software family, so it is the intended answer.