Solve the following equation by completing the square.

$3x^2+x-\frac{1}{12}=0$

Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A$.$ The solution set is $\{$

$($Simplify your answer, including any radicals. Use integers or fractions for any numbers in the expression. Use a comma to separate answers as needed.$)$

B$.$ There is no solution.