Option D: The original balance on the credit card.
Step-by-step explanation:
Let x represents the number of months.
Let y represents the money owned.
The y-intercept of a model can be determined when x = 0.
In other words, the y-intercept is the value of y when x = 0.
Thus, from the data, it is obvious that when x = 0, the value of y is $2000.
Thus, the y-intercept is $2000.
Thus, the y-intercept represents the original balance on the credit card.
Hence, Option d is the correct answer.