If the roots of the following quadratic equation exist,find them by the method of completing the square: $3x^2 + 7x + 5 = 0$.

• A
  Roots exist and are $x = \frac{-7 \pm \sqrt{11}}{6}$
• B
  Roots exist and are $x = \frac{-7 \pm \sqrt{11}}{3}$
• C
  Roots do not exist
• D
  Roots exist and are $x = \frac{-7 \pm \sqrt{11}}{2}$