5. A 3-line to 8-line decoder is connected as shown, where x, y, and z are inputs (z is the least significant input digit) and F is an output. F = 1 when

  1. All 3 inputs are logical 0
  2. 2 out of 3 inputs are logical 0
  3. 1 out of 3 inputs are logical 0
  4. No input is logical 0
  5. None of the above

5 is WRONG. Hint: Construct a truth table and look at the input conditions in rows 3, 5, and 6. Each of these rows possesses two ones and one zero.

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