Explanation

In 4-bit 2's complement arithmetic, 5 is 0101 and −3 is 1101; adding them gives 0101 + 1101 = 10010. The leading 1 is the carry out of the 4-bit adder — discarding it leaves 0010, i.e., decimal 2, the correct result of 5 − 3. The full adder output 10010 is option B.