If the graph of \(y=x^2\) is reflected across the \(x\)-axis, what is the equation of the resulting graph?

Correct answer: \(y=-x^2\)

Reflection across the \(x\)-axis maps every point \((x,y)\) to \((x,-y)\). Thus the parabola \(y=x^2\), which opens upward, becomes \(y=-x^2\), which opens downward. Option B is the unchanged original graph, not its reflection. Exam tip: reflection in the \(x\)-axis changes the sign of \(y\); reflection in the \(y\)-axis changes the sign of \(x\).