Answer:
AC
Step-by-step explanation:
The positions of the corresponding sides in both triangles match, that is
AB → XY
AC → XZ
BC → YZ
Since the triangles are similar then the ratios of corresponding sides are equal, so
[tex]\frac{BC}{YZ}[/tex] = [tex]\frac{AC}{XZ}[/tex] = [tex]\frac{AB}{XY}[/tex]