Final answer:
True, an auditor may reduce substantive tests when assessed control risk has been lowered based on effective tests of controls.
Step-by-step explanation:
When an auditor has reduced assessed control risk based on tests of controls, it is indeed true that they may reduce the extent to which the accuracy of the financial statement information directly related to those controls must be supported through the accumulation of evidence using substantive tests.
Control risk refers to the risk that a misstatement that could occur in an account will not be prevented or detected and corrected on a timely basis by the entity's internal controls. When an auditor assesses this risk to be lower, generally because the controls have proven to be effective, the auditor can opt to perform less substantive testing since the reliability on control procedures has increased.