If the following system has non-trivial solution,

px + qy + rz = 0 qx + ry + pz = 0 rx + py + qz = 0

then which one of the following options is True?

A | p – q + r = 0 or p = q = –r |

B | p + q – r = 0 or p = –q = r |

C | p + q + r = 0 or p = q = r |

D | p – q + r = 0 or p = –q = –r |