Final answer:
In macro definitions, arguments must be surrounded by parentheses. The #define directive is used in languages like C and C++ for this purpose, ensuring correct expression evaluation when the macro is used.
Step-by-step explanation:
When setting up arguments for macros in the macro definition, arguments must be surrounded by parentheses (()). In programming languages like C and C++, a macro is a fragment of code which has been given a name. When the name is used, it is replaced by the contents of the macro. For example, to define a macro with arguments, you would use the #define directive followed by the macro name and the arguments in parentheses.
Here is how you might define a simple macro that adds two numbers:
#define ADD(x, y) ((x) + (y))
The arguments 'x' and 'y' are surrounded by parentheses to ensure that when the macro is used, the passed expressions are evaluated correctly without being affected by operator precedence.