Let's begin by listing out the information given to us:
1.
[tex]\begin{gathered} 5\sqrt[]{11}-12\sqrt[]{11}-2\sqrt[]{11} \\ \Rightarrow(5-12-2)\cdot\sqrt[]{11}_{} \\ \Rightarrow-9\cdot\sqrt[]{11} \\ \Rightarrow-9\sqrt[]{11} \end{gathered}[/tex]
Therefore, the third option is the correct answer
