Interest on capital is calculated as: \[ \text{Interest on Capital} = \text{Capital Amount} \times \text{Rate of Interest}. \] Assume Vivek's capital is ₹3,80,000, and the rate of interest is 15% per annum: \[ \text{Interest on Capital} = ₹3,80,000 \times 15% = ₹57,000. \] Thus, the correct answer is (C).