The roots of $3x^2 + 7x + 1 = 0$ are —

• a$\dfrac{-7 \pm \sqrt{37}}{6}$
• b$\dfrac{7 \pm \sqrt{37}}{6}$
• c$\dfrac{-7 \pm \sqrt{49}}{6}$
• d$\dfrac{-7 \pm \sqrt{13}}{6}$