The correct answer is B) 90° apart. When repacking a reciprocating pump with more than four rings of packing, the packing is cut square, installed with the ends abutted, and each succeeding ring staggered with the butted ends 90° apart. This staggered placement of the packing rings helps to create a better seal and prevent leaks by interrupting the path of the fluid flow. The other options are incorrect because 45° would not provide enough staggering, 120° would be too much staggering, and 180° would place the joints directly opposite each other, which would not effectively interrupt the fluid path.