Explanation

Starting with the question, we note that, if we knew Celine's hourly rate, we would know how much money she made. If we knew her total money, we'd be able to find her hourly rate. Either of those outcomes would be useful. On to the data statements, separately first.

Statement (1) says that her pay is $430. That means that



So we can compute the hourly rate. And once we have that, we could decrease it by $2.50 and divide it into $430 to see how many hours Celine would have to work in order to make $430 still. Therefore Statement (1) is sufficient.

Statement (2) basically tells us what Celine's currently hourly rate is. 10% of the rate is $2.15. And from the prior statement, we learned the lesson that the hourly rate is sufficient information here. We can't bring data from Statement (1) when we look at Statement (2), but frequently there is a lesson learned from one of the statements that we can apply quickly to the other one. So Statement (2) is sufficient.

The correct answer is (D).