At Tom Nook Banking, the new data processing manager noticed that typically the bank processed over 100,000 checks per day, and that because of the high volume there had been errors that went undetected until too late. In order to make sure that all these checks are correctly processed by the computer, they created separate groups of 1,000 checks each and prepared a document to serve as a control on the contents of each group. Which internal control is this an example of?

1.) Edit test

2.) Hash total

3.) Check digit

4.) Batch control total