Please help me answer this question please

Step-by-step explanation:
100% = $2000
1% = 100%/100 = 2000/100 = $20
the gain was 2056.72 - 2000 = $56.72
how many % is that compared to the original $2000 ?
56.72 / 20 = 2.84%
so, C is the right answer.