Answer: a. added to Inventory.
Step-by-step explanation:
A Perpetual Inventory system is one where the inventory records of a company are updated as soon as inventory is either received or sold thus ensuring that the inventory balance is more accurate.
When using a perpetual inventory system, a key feature is that the transportation costs of the inventory are added to the inventory as part of the costs of acquiring the inventory unlike with the periodic system where a separate account will be maintained.