Look at the figure shown below:

Which step should be used to prove that point P is equidistant from points R and Q?
A. Using AAS postulate, prove that triangles PQS and PRS are congruent.
B. Using SAS postulate, prove that triangles PQS and PRS are congruent.
C. Using ASA postulate, prove that triangles PQS and PRS are similar triangles.
D. Using AAA postulate, prove that triangles PQS and PRS are similar triangles.