Final answer:
When using the income approach in appraisal, appraisers assume that buyers estimate the duration of income when buying income property, future income is always less valuable than present income, and the value is directly related to income. Option d.
Step-by-step explanation:
The correct answer is d. all of the above. When using the income approach in appraisal, appraisers assume that buyers estimate the duration of income when buying income property, future income is always less valuable than present income, and the value is directly related to income. These assumptions help appraisers determine the value of income-generating properties by considering the income potential and the expected return on investment.