A deposit required under Section 406.003 must be made with the comptroller and approved by the commissioner. The deposit must be made in:
(1) cash;
(2) securities authorized under this code to be a legal investment for the insurer that:
(A) are readily marketable over a national exchange with a maturity date of not more than one year, are listed by the Securities Valuation Office of the National Association of Insurance Commissioners, and qualify as admitted assets; or
(B) are clean, irrevocable, and unconditional letters of credit issued or confirmed by a financial institution organized and licensed under the laws of the United States or a state of the United States; or
(3) another form of security acceptable to the commissioner.