12-bit 2's complement of -73.75 is -

To find the 12-bit 2's complement of -73.75, we first convert the positive magnitude 73.75 to binary. The integer part 73 is $64 + 8 + 1$, which equals $01001001_2$. The fractional part 0.75 is $3/4$, which equals $.11_2$. Combining these gives the positive binary form $01001001.11_2$. To represent this as a negative number in 2's complement, we invert all bits to get $10110110.00_2$ and then add 1 to the least significant bit (LSB). Adding $0.01_2$ to the fractional part results in $.01_2$. Thus, the final 12-bit representation is $10110110.01_2$. Option C matches this result exactly. Option A is incorrect because it starts with 0, representing a positive number (+73.75). Option B is incorrect because it represents -42.25, not the target value.