Explanation:

- Selling Price of A is 25% less than Selling Price of B: This means if B’s selling price is Rs. 100, A's selling price is Rs. 75.

- B earns a profit of Rs. 160 with a profit percentage of 20%: This allows us to calculate B's cost price. Let CP of B be X.

- Selling Price of B = CP of B + Profit

- 1.20X = X + 160

- 0.20X = 160

- X = Rs. 800 (Cost Price of B)

- Cost Price of A can be calculated using A's Selling Price:

- SP of A = 0.75 x SP of B

- SP of A = 0.75 x 1.20 x 800 = Rs. 720

- Profit for A = 20%, so:

- CP of A = SP of A / 1.20 = Rs. 720 / 1.20 = Rs. 600

- Correct Option: Option 3 - Rs. 600