To list a variable number 16 times without typing 16 lines of code, which technique should you use?

Using looping is the most efficient technique for listing a variable multiple times, such as 16 times, without needing to write the same line of code repeatedly. A loop allows you to iterate through a block of code a specified number of times, thus significantly reducing redundancy and enhancing code maintainability.

For instance, a simple loop structure can be set up to execute a command or output a variable 16 times consecutively. This approach not only saves time during initial coding but also makes future modifications easier; changing the number of iterations requires altering just one part of the code rather than 16 separate lines.

In contrast, an if-then structure is used for conditional execution, which does not lend itself to repetitive tasks like listing a number multiple times. Environmental variables deal with configurations and settings for the execution environment, and comment syntax is intended for notes within the code rather than for executing commands. Therefore, while each alternative has its specific function, looping is clearly the most suitable option for efficiently repeating an action multiple times.