Triangle pqr has been dilated to form triangle p'q'r'. what is the least amount of information needed to determine if the two triangles are similar?

a. segments pr and p'r' are congruent, and segments qr and q'r' are congruent.

b. angle r=r', angle q=q', and segments qr and q'r' are congruent.

c. segment qr=q'r', segment pr=p'r', and angles q and q' are congruent.

d. angles q and q' are congruent, and angles r and r' are congruent.