Caleb made the table below to show the number of hours he works and the amounts he earns over a four-week period. Which describes whether the relationship between the earnings and the number of hours represents a direct variation?
A. He earns 20 more than 10 times the number of hours he works each week, so the earnings vary directly with the hours.
B. The earnings increase by 30 for every increase of 3 hours, so the earnings vary directly with the hours.
C. The ratios of earnings to hours are not the same each week, so the earnings do not vary directly with the hours.
D. The earnings increase at a steady rate, so the earnings do not vary directly with the hours.