Below circuit of gate in (RTL) resistor transistor logic

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Below circuit of gate in (RTL) resistor transistor logic family. The circuit represents—

1. NAND
2. AND
3. NOR
4. OR

Correct Option: D

(i) V₁ = O and V₂ = O ⇒ Q₁ = Q₂ = OFF,
VB = VCE₁ = VCE₂ = VCC
Q₃ = ON, V_O = O
(ii) V₁ = O and V₂ = 1 ⇒ Q₁ = OFF, Q₂ = ON, VB = Q₃ = OFF
or V_O = 1
(iii) V₁ = 1 and V₂ = O
⇒ Q₁ = ON, Q₂ = OFF, VB = VCE₂
⇒ Q₃ = OFF V_O = 1
(iv) V₁ = 1 and V₂ = 1 ⇒ Q₁ = Q₂ = ON, VB = O ⇒ Q₃ = OFF
V_O = VCE₃ or V_O = 1
Hence truth table:

Hence the, circuit represent the relation
⇒ V₀ = V1 + V2
⇒ OR gate.
Hence alternative (D) is the correct answer.