What defines the semantic rule in programming?

The semantic rule in programming pertains specifically to the meaning and behavior of the instructions and expressions within a program. This aspect of programming deals with what a piece of code does when it is executed, effectively translating the written code into meaningful actions and results.

For example, if an instruction tells the program to add two numbers together, the semantics define that the operation should produce a sum, not just a series of commands. This meaning includes how data is manipulated and how different statements interact with one another in the context of the overall logic of the program.

In contrast, the other aspects mentioned in the options focus on different areas of programming. Variables being declared refers to syntax rather than meaning, the order of operations addresses precedence rules for evaluating expressions, and structures of loops and conditionals pertain to the flow of control in a program—all of which are important but do not directly pertain to the meaning behind the programming instructions themselves.