194  US 9,217,919 B2  193  -continued  oyo~ 0  oyo~ 0  oyo~ 0  (III-1)  the ionic structural site of the repeating unit (A) contained  in the resin (P) is a structure capable of generating an  acid in a side chain of the resin upon irradiation with an  actinic ray or radiation;  the repeating unit (A) is a repeating unit represented by  general formula (III-1) or (III-4):  a repeating unit (B) having at least one phenolic hydroxyl  group, a part or all of hydrogen atoms of the hydroxyl  group or groups each being protected by a group capable  of leaving by the action of an acid,  a repeating unit (A) having an ionic structural site and  capable of decomposing upon irradiation with an actinic  ray or radiation to generate an acid; and  wherein  a resin (P) having  20.  A radiation-sensitive composition comprising:  19.  The radiation-sensitive composition according to claim  17,  wherein the repeating unit (C) represented by the general  formula (VI) is selected from the group consisting of the  following repeating units:  -continued  oyo~ 0  oyo~ 0  OH  OH. 