Answer:
a)
Explanation:
Since the worksheet contains most of the data that you need, there is a decent possibility that it also contains the data that you are missing. Therefore, you should check for data you have previously hidden. Sometimes, some data in a worksheet may become irrelevant in a given moment, and instead of deleting it since it may be useful later most people tend to make that data hidden. So checking for previously hidden data may be the best solution in this scenario.
