Answer:
B. -1/12
Step-by-step explanation:
1/2 - 5/6 + 1/4 = -1/12
[tex] \frac{1}{2} - \frac{5}{6} = \frac{3}{6} - \frac{5}{6} = - \frac{2}{6} \\ \\ = - \frac{1}{3} + \frac{1}{4} = - \frac{4}{12} + \frac{3}{12} = - \frac{1}{12} [/tex]