Stephen and Andrea have recently been assigned to the audit of Duck Enterprises, a manufacturer or personal and commercial fishing products. The pair are deciding how best to audit the clients system of internal controls. Which of the following choices correctly represent considerations for Stephen and Andrea with respect to internal controls?

a) How long it will take the auditing firm to find a specialist to audit the clients system of internal controls.

b) To what extent should internal controls be tested, and how much time will be needed to effectively audit the population of transactions.

c) How easy it will be to obtain written assurances from senior management pertaining to internal control, to include in the audit file and as part of the audit opinion.

d) Which controls should be selected for testing, and when the most appropriate time for testing those controls may be.