The combination of gates shown in the figure below produces.

• A

  NOR gate
• Correct answer
  B

  OR gate
• C

  AND gate
• D

  XOR gate

Solution

Outputs of different gates are shown below



$\therefore$ output of the combinations

$Y=\overline{\overline{A}.\overline{B}}=A+B$

This is the expression of $OR$ gate.

Hence, the correct answer is option: 'B'.