Which of the following statements does not prop- erly describe a limitation of an audit?

a. Many audit conclusions are made on the basis of examining a sample of evidence..

b. Some evidence supporting dollar representa- tions in the financial statements must be ob- tained by oral or written representations of man- agement.

c. Fatigue and carelessness can cause auditors to overlook pertinent evidence.

d. Many financial statement assertions cannot be audited.