[tex]\begin{gathered} A(-3,4) \\ B(0,1) \\ C(4,2) \\ \text{ reflection across the y ax}is\text{ } \\ B(0,1)\rightarrow B\text{'(0,1)} \end{gathered}[/tex]
The reflection across the y axis the x value changes sign but the y value remain the same.
The answer is C
