A bank wants to reject erroneous account numbers to avoid invalid input. Management of the bank was told that there is a method that involves adding another number at the end of the account numbers and subjecting the other numbers to an algorithm to compare with the extra numbers. What technique is this? 1. Optical character recognition (OCR) software. 2. Self-checking number. 3. Validity check. 4. Field (format) check.

A bank wants to reject erroneous account numbers to avoid invalid input. Management of the bank was told that there is a method that involves adding another number at the end of the account numbers and subjecting the other numbers to an algorithm to compare with the extra numbers. What technique is this? 1. Optical character recognition (OCR) software. 2. Self-checking number. 3. Validity check. 4. Field (format) check.