Answer: (C)
Explanation: Overflow indicates that the result was too large or too small to fit in the original data type.
Overflow flag indicates an overflow condition for a signed operation. Signed numbers are represented in two’s complement representation.
The overflow occurs only when two positive number are added and the result is negative or two negative number are added and the result is positive. Otherwise, the sum has not overflowed.
Therefore, a XOR operation can quickly determine if an overflow condition exists. i.e.,
(A7 . B7 )⊕(S7) = (A7 . B7 . S7‘ + A7‘ . B7‘ . S7 = 1
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