A triangle, ABD, is reflected across the y-axis to have the image ABD in the standard (x,

A triangle, ΔABD, is reflected across the y-axis to have the image ΔA′B′D′ in the standard (x, y) coordinate plane: thus A reflects to A′. The coordinates of point A are (m, n). What are the coordinates of point A′?
F. (−m, n)
G. (m,−n)
H. (−m,−n)
J. (n, m)
K. Cannot be determined from the given information.