please explain how you you get to the final number

During the taxation year, Sherry earned $10,000 in wages and recelved $1,500 in tips from her part-time job as a waitress. From the RESP that her grandfather had established for her, she recelved $6,000 in investment income and $1,000 in capital. She withdrew $5,000 from her RRSP. She also recelved $3,000 in EI payments. What is Sherry's taxable income? a) $15,000 b) $21,000 c) $22,500 d) $25,500