Correct Option: C

The given circuit

Given, R_L = R = 1Ω
Equivalent circuit for calculation of R_th is shown below:

From figure, R_th = (1|| 1) + (1||1) = 1/2 + 1/2 = 1Ω
Equivalent circuit for calculation of Vth is shown below:

Applying KVL in the loop 1, we get
– I₁ × 1 + 1 – I₁ × 1 – 1 = 0
or
I₁ = 0
Again, applying KVL in the loop 2, we get
1 – I₂ × 1 – I₂ × 1=0
or
I₂ = 1/2 A
Now, V_th = 1 × I₁ + 1 × I₂ = 1 × 0 + 1 × 1/2 = 1/2 V
Now,

I2 =	Vth	6 + 5	=	0.5	=	0.5	= 0.25A
		Rth + RL		1 + 1		2

Hence alternative (C) is the correct choice.