Choose the One Alternative That Best Completes the Statement or Answers

Multiple Choice

Choose the one alternative that best completes the statement or answers the question.
Use the quadratic formula to solve the equation. (All solutions are real numbers.)
- $\frac{z^{2}}{3}=\frac{z}{2}+\frac{5}{6}$

A) $\left\{-1, \frac{5}{2}\right\}$

B) $\left\{\frac{3+2 \sqrt{10}}{4}, \frac{3-2 \sqrt{10}}{4}\right\}$

C) $\left\{\frac{5}{2}\right\}$

D) $\{-1\}$