Which term refers to the variables passed to a function or procedure at the time of invocation?

The term that refers to the variables passed to a function or procedure at the time of invocation is known as "actual parameter." When you call a function, you provide specific values or references to variables, which are then used by that function. These are the actual data that get passed in and used during the execution of the function.

In contrast, formal parameters refer to the variables defined in the function's declaration; they act as placeholders for the data that will be supplied (the actual parameters) when the function is called. Default parameters are special parameters that allow a function to be called with fewer arguments than it is defined to accept, while static parameters relate to variables that maintain their value even after the function execution has completed, which isn't relevant to the distinctions we have here. Thus, the correct term for the data passed during the call of a function is "actual parameter."