An expense report was prepared by a company's cost center. One executive questioned one of the amounts and asked for "the source documents which support the total.$$ Data processing was not able to routinely do so$.$ The best control procedure would be:

Question $9$ options:

a$)$

Producing an error listing to check the expense

b$)$

Documentation of the expense amount questioned by the executive

c$)$

Transmittal control the expense amount questioned by the executive

d$)$

Tracing the transaction details that relate to the expense