Devin's older sister showed him the following math trick:

"Think of a number. Multiply it by 6, now add 12. Divide by 6. Now subtract your original number. I bet your answer is 2!"

Devin wanted to figure out how this trick worked, so he used deductive reasoning to make the following argument:

1. n = my number.

2. The number changes according to the expression $\displaystyle\frac{{{6}{n}+{12}}}{{6}}-{n}\usepackage{cmbright}\Huge\$

4. So the result is always 2.

Which of the following arguments best connects points 2 and 4?