Final answer:
The auditor is trying to satisfy the balance-related audit objective of existence by reviewing the receivables listed on the aged trial balance for notes and related party receivables.
Step-by-step explanation:
The auditor is reviewing the receivables listed on the aged trial balance for notes and related party receivables in order to satisfy the balance-related audit objective of existence. This objective ensures that the receivables actually exist and are valid. By reviewing the receivables and tracing them to supporting documentation, the auditor can confirm their existence and accuracy.