Which of the following describes a unique characteristic of interpreted languages?

Interpreted languages have a unique characteristic in that they require an interpreter to execute the code directly at runtime. This means that as long as the correct interpreter is available on a machine, the code can be executed regardless of the underlying hardware or operating system. This feature provides a significant level of portability and flexibility, enabling developers to write code that can be easily run on multiple platforms without needing to compile it for each specific one.

The other options do not accurately reflect the defining traits of interpreted languages. For instance, graphical diagrams refer to visual representations of data or processes, which is not inherently tied to the execution of interpreted languages. Compilation to machine code is characteristic of compiled languages, not interpreted ones. While object-oriented programming is supported in many interpreted languages, it is not a unique feature that sets them apart from compiled languages. Thus, the ability of interpreted languages to run on any machine with the appropriate interpreter highlights their distinctive nature.