Final answer:
The correct proportion to show that ∆WXZ is similar to ∆XYZ is (A) WX/XY = XZ/YZ, as it compares the corresponding legs opposite the congruent right angles, satisfying the SAS Similarity Postulate.
Step-by-step explanation:
The question concerns the proof of similarity between two triangles, ∆WXZ and ∆XYZ, using the SAS Similarity Postulate. To complete the proof, we must show that the corresponding sides of the two triangles are in proportion. Given that triangles ∆WXZ and ∆XYZ are right triangles sharing the right angle at XZ, and that we are provided with the lengths WZ (10), XZ (5), and YZ (2.5), the correct proportion is (A) WX/XY = XZ/YZ. This proportion compares the length of the legs opposite the congruent right angles in each triangle, which is the necessary condition to use the SAS Similarity Postulate. Here WX and XY are the legs opposite the right angles in their respective triangles.