C.P. = ₹ 150 and loss = 50% ⇒ the S.P. is:

1. ₹ 200

2. ₹ 100

3. ₹ 225

4. ₹ 75

Given:

C.P. = ₹ 150

Loss % = 50%

$\text{Loss \%} = \dfrac{\text{Loss}}{\text{C.P.}} \times \text{100}$

Putting the values, we get

$\Rightarrow\text{50} = \dfrac{\text{Loss}}{150} \times 100\\[1em] \Rightarrow\text{Loss} = \dfrac{50 \times 150}{100} \\[1em] = \dfrac{7500}{100} \\[1em] = 75$

As we know:

$\text{Loss} = \text{C.P. - S.P.}\\[1em] \Rightarrow 75 = 150 - \text{S.P.}\\[1em] \Rightarrow \text{S.P.} = 150 - 75\\[1em] \Rightarrow \text{S.P.} = 75$

Hence, option 4 is the correct option.