An OR gate has 6 inputs. What is the only input word that produces a 0 output? A. 0 B. 111 C. 111000 D. 111111 E. None of the above

The correct answer is $\boxed{\text{A. }0}$.

An OR gate produces a 1 output if any of its inputs are 1. Therefore, the only input word that produces a 0 output is 0, since all other input words have at

Option $\text{B. }111$ produces a 1 output, since all of its inputs are 1.

Option $\text{C. }111000$ produces a 1 output, since the first five inputs are 1 and the sixth input is 0.

Option $\text{D. }111111$ produces a 1 output, since all of its inputs are 1.

Option $\text{E. }None of the above$ is correct, since there is only one input word that produces a 0 output.