GKFix MCQ Question

How much work is required to bring the third charge (+q) to point C?

• A. \frac{q^2}{4\pi\epsilon_0 d} \left(1 - \frac{1}{\sqrt{2}}\right)
• B. \frac{q^2}{4\pi\epsilon_0 d} \left( \frac{1}{\sqrt{2}} - 1 \right)
• C. \frac{q^2}{4\pi\epsilon_0 d\sqrt{2}}
• D. -\frac{q^2}{4\pi\epsilon_0 d}