Marilyn is 60 years old. She earned the following interest income during the current year of assessment: - Interest received from South African bank of R25 300 - Interest received from a South African tax-free savings account of R18 700 - Interest received from a foreign bank account of R20 000 YOU ARE REQUIRED to determine the total amount which will be exempt (include the tax free investment in your answer) when determining Marilyn's taxable income for the current year of assessment. Select one: a. R25 300 b. R42 500 c. R64000 d. R44000