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The logic realized by circuit shown in figure below is—

1. F = A ⊕ C
2. F = A ⊕ C
3. F = B ⊕ C
4. F = B ⊕ C

Correct Option: B

In 4 × 1 MUX, A and B as select line, the truth table is

Output = F = I₀ – S₁ – S₂ + I₁ – S₂ S₁
F=I₀ – S₁ – S₂ + I₁ – S₁ S₂ + I₂ – S₁ S₂ + I₃ S₁S₂
= C – A – B + C – A B + – C A – B + – C A B
= C – A (B + – B) + – C A (– B + B)
= C – A + – C A
= C ⊕ A