The suggested answer is A.
To execute the search macro defined as convert_sales(3), one should pass the arguments as plain text without enclosing them in additional characters. The macro accepts three arguments: 'currency', 'symbol', and 'rate'. The correct syntax is to call the macro by its name followed by the arguments in parentheses, separated by commas. Thus, the correct execution would be convert_sales(euro,€,0.79).