Final answer:
The correct answer to the question is A) The increase in pay as the time spent babysitting increases, which represents a proportional relationship between time and earnings.
Step-by-step explanation:
The student's question about Steven's earnings through babysitting demonstrates a scenario of a proportional relationship between two quantities: the amount charged and the time spent babysitting. The answer that correctly reflects this relationship is A) The increase in pay as the time spent babysitting increases. In a proportional relationship, as one quantity increases, the other increases at a constant rate, which means that as Steven babysits for more hours, his earnings will rise proportionally. In contrast, options B, C, and D suggest non-proportional scenarios with inconsistent, decreasing, or irregular payment structures.