Simplify the following exprossion If the expression cannot be simplifect, se state) \[ \sqrt{63} \] Select the correct choice below and, if mecessary, ill in the answer box to complete your choin A. \( \sqrt{63}= \) \( \square \) (Type an oxact answer, using radicals as noeded) B. The expression cannot be simplified

**A.** \( \sqrt{63} = 3\sqrt{7} \) **Explanation:** To simplify \( \sqrt{63} \), factor 63 into its prime factors: \[ 63 = 9 \times 7 \] Since 9 is a perfect square (\( 9 = 3^2 \)), you can simplify the square root as follows: \[ \sqrt{63} = \sqrt{9 \times 7} = \sqrt{9} \times \sqrt{7} = 3\sqrt{7} \] Therefore, the simplified form of \( \sqrt{63} \) is \( 3\sqrt{7} \).