$3-39$ Which of the following is a reason that the auditor obtains an understanding of the client$$s internal control over financial reporting?

a$.$ This understanding is required by professional auditing standards.

b$.$ Understanding of internal control is needed to properly plan the audit.

c$.$ This understanding helps an auditor assess a client$$s risk of material misstatement.

d$.$ All of the above are reasons why the auditor obtains an understanding of the client$$s internal control over financial reporting.