Solve. \[ \sqrt{1-3 x}=8 \] Select the correct choice below and, if necessary, fill in the answer box to complete your choice. A. The solution(s) is/are (Type an integer or a simplified fraction. Use a comma to separate answers as needed.) B. There is no solution.

To solve the equation \( \sqrt{1-3x} = 8 \), we first square both sides: \[ 1 - 3x = 64 \] Next, we isolate \(x\): \[ -3x = 64 - 1 \] \[ -3x = 63 \] \[ x = -21 \] Now, we can check if our solution is valid by substituting \(x = -21\) back into the original equation: \[ \sqrt{1 - 3(-21)} = \sqrt{1 + 63} = \sqrt{64} = 8 \] Since it holds true, we have found a solution. A. The solution(s) is/are -21