What must be executed with the same formalities as a will?

A codicil is an amendment or addition made to an existing will, and it must be executed with the same formalities as the original will. This means that a codicil needs to be written, signed by the testator (the person who made the will), and witnessed in accordance with the laws governing wills in Florida. The requirement for formal execution ensures that the codicil holds the same legal weight as the original will, maintaining the integrity of the testator's intentions.

While affidavit, power of attorney, and trust deed are important legal documents, they do not require the same formalities as a will or a codicil. An affidavit is typically a sworn statement, a power of attorney allows someone to act on another's behalf but does not require witnessing in the same manner as a will, and a trust deed involves the transfer of property into a trust but also does not follow the same execution requirements as a will. Therefore, the unique requirement for a codicil to be executed with identical formalities as the original will is what makes it the correct answer.