<prompt> Which of the following is used for permanent interstitial implant brachytherapyBoronCesium 131PhosphorusIridium  <response>: Permanent implants of interstitial brachytherapy :- Cesium -131, Yttrium, Gold - 198 Au - 198, 125I, Radon - 222 Rn - 222, Pallidum -103 Pd -103.Temporary implants of Interstitial brachytherapy :- Iridium - 192 Ir - 192, Cesium - 137 Cs - 137, Cobalt - 60 Co - 60, Californium, Radium - 226 Ra - 226, Tantolum. 