Final answer:
A completed gift is made by transferring assets to an irrevocable trust with Crummey Provisions, since such a trust cannot be altered by the grantor, signifying the relinquishment of control over the assets.
Step-by-step explanation:
A completed gift in the context of estate planning involves transferring assets in such a way that the donor relinquishes control over the assets. Among the options given, a completed gift is made in transferring assets to an irrevocable trust with Crummey Provisions.
An irrevocable trust, once established, generally cannot be altered or terminated by the grantor, hence the assets are considered to be out of the grantor's control and constitute a completed gift for tax purposes. On the other hand, a revocable trust allows the grantor to retain control over the assets and can be changed or terminated at any time before the grantor's death, therefore it does not constitute a completed gift. A complex trust may refer to the tax treatment of a trust and does not inherently determine whether a gift is completed.