A Logical Sampling Unit is defined as:
a) The item snagged by the sampling plan for audit, such as an individual customer, or individual sales invoice. Tests of controls are performed on the logical sampling unit.
b) The item snagged by the sampling plan for audit, such as an aggregated group of customers, or sales invoices. Auditing procedures are performed on the logical sampling unit.
c) A department within the client's firm, which will be audited by the external auditor.
d) The item snagged by the sampling plan for audit, such as an individual customer, or individual sales invoice. Auditing procedures are performed on the logical sampling unit.