No, you got the inequalities the wrong way.
In negative numbers, it is how much lower it is than 0. For example, -22 is 22 less than 0. And -2 is 2 less than 0. Here, -22 is actually less than -2 because it is farther below 0 than -2.
You can understand this better if you graph it on a number line.
So, -12 >-15. (-15 is 3 less than -12).
-1/3 >-1.
-2>-21.
A radical is also known as a square root. An example of a radical is √25 or ∛36.
Not too sure but i think it’s D