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Shift control CLK SI SO Shift register A (Augend) FA Serial input SI SO Shift register B (Addend) Clear For the circuit shown above, assume the initial contents of registers A and B are 1110 and 1111, respectively. What are the initial of S and C before applying any clock pulses? S = 1, C = 0 S = 0, C = 1 Undetermined S = 0, C = 0 S = 1, C = 1