Which of the following meets the requirements of a gift subject to the gift tax?

Question 15 options:

A donor writes a check for $20,000 payable to the donee who cashes the check when it arrives in the mail.

A donor writes a check for $20,000 payable to the donee. The donee receives the check and accidentally tears it up.

A donor writes a check for $20,000 payable to the donee and forgets to mail it.

A donor misplaces a check. The donee finds the check and endorses to himself for $20,000.