To simplify \(\sqrt{170}\), we start by factoring 170 into its prime factors:
\[ 170 = 2 \times 5 \times 17 \]
Since there are no perfect squares among the factors, we cannot simplify further. Therefore, the simplest form of \(\sqrt{170}\) is:
\[ \sqrt{170} \]
So the correct response is:
This radical expression is already fully simplified.