Which of the following best completes the proof showing that ΔWXZ ~ ΔXYZ? triangles WXZ and XYZ that share side XZ with right angle XZW, WZ equals 16, XZ equals 12, and YZ equals 9

Since segment XZ is perpendicular to segment WY, angles WZX and XZY are both right angles and congruent. The proportion shows the corresponding sides are proportional, so the triangles are similar by the SAS Similarity Postulate.

16 over 12 equals 9 over 12
16 over 12 equals 12 over 9
12 over 12 equals 16 over 9
12 over 16 equals 16 over 9