Which of the following is not a PLC Programming Language?

The correct answer is that "Global function chart" is not considered a PLC programming language. In the context of PLC programming, established languages are defined by the IEC 61131-3 standard, which includes Ladder Diagram, Structured Text, Function Block Diagram, Sequential Function Chart, and Instruction List.

Ladder Diagram mimics electrical relay logic in a graphical format, making it a popular choice for programming PLCs, especially among those with an electrical background. Structured Text is a high-level programming language that resembles traditional programming languages like Pascal and is useful for complex algorithms and data manipulation. Instruction List, although less common now, is a low-level text-based programming language also defined in the IEC 61131-3 standard.

On the other hand, "Global function chart" is not a programming language for PLCs but rather a concept that refers to a chart utilized within the context of another language, specifically as a graphical representation that can be integrated with other programming methods. This distinction makes it clear why it is excluded from the list of recognized PLC programming languages.