Orders of Magnitude are in terms of scientific notation.
23,000 written in scientific notation is 2.3 x 10^4, it's magnitude is 4 ( the number 10 is raised to)
56 in scientific notation would be 5.6 x 10^1, its magnitude is 1.
4 - 1 = 3
2300 is 3 order of magnitudes larger.
The answer is 3.