Hi!
The correct options would be:
It is a set of step-by-step instructions.
It is called code.
It tells a computer exactly what to do.
A computer program, or a program code, is a set of clearly defined instructions in a language that the computer understands. This set of instructions tasks the computer on what actions to perform and in what manner, and are not for the users on the operation of a computer.
Hope this helps!
