Control totals include batch totals, hash totals, and record counts. Which of these totals would be useful in preventing or detecting IT system input and processing errors or fraud described as follows?

a. A payroll clerk accidentally entered the same time card twice.

b. The accounts payable department overlooked an invoice and did not enter it into the system because it was stuck to another invoice.

c. A systems analyst was conducting payroll fraud by electronically adding to his “hours worked” field during the payroll computer run.

d. To create a fictitious employee, a payroll clerk removed a time card for a recently terminated employee and inserted a new time card with the same hours worked.