C m
10 80
20 160
30 240
40 320

Ramsey's dad owns a dairy farm. The table shows the relationship between the number of cows, c, and the gallons of milk, m, produced each day.

Based on this information, which is the independent variable and the dependent variable?
A) Both cows and milk are independent variables.
B) Both cows and milk are dependent variables.
C) The independent variable is milk, and the dependent variable is cows.
D) The independent variable is cows, and the dependent variable is milk.