Choice A is the correct answer. The quadratic formula is $x = \frac{-b \pm \sqrt{\Delta}}{2a}$.

• Here $a=2$, so the denominator should be $2(2) = 4$.
• The student used 2, likely forgetting to multiply by $a$.

Choice B is incorrect because $-(-4) = 4$ is correct. Choice C is incorrect because $\Delta = (-4)^2 - 4(2)(-3) = 16 + 24 = 40$ is correct. Choice D is incorrect because the denominator is definitely wrong.