Answer:
Binary code
Step-by-step explanation:
Code is a word or a symbol which is not disclosed to everyone and is considered as secretive. There are various codes which are required to run a software in order to minimize the risk of piracy. These codes are binary codes or java codes. These are complex so that not everyone can crack it.
The first rule you need to know is

So, you have

The second rule you need to know is

So, you have

The fourth answer is correct. When dividing by x to the half (aka square root of x), divide every power of x by two.