For two triangles, △PQR and △XYZ, which of the following sets of conditions is not sufficient to prove that △PQR≅△XYZ?
PQ=XY, ∠Q=∠Y, QR=YZ
∠P=∠X, ∠Q=∠Y, ∠R=∠Z
PQ=XY, QR=YZ, RP=ZX
∠P=∠X, ∠Q=∠Y, QR=YZ
