Steve invested $100 two years ago at 10 percent interest. The first year, he earned $10 interest on his $100 investment. He reinvested the $10. The second year, he earned $11 interest on his $110 investment. The extra $1 he earned in interest the second year is referred to as: A. free interest. B. bonus income. C. simple interest. D. interest on interest. E. present value interest