Benefits payable to participants under the optional retirement program are not obligations of the State of Mississippi. Those benefits and other rights of optional retirement program participants or their beneficiaries are the liability and responsibility solely of the designated company or companies. The benefits of participants whose funds are invested with annuity providers shall be governed solely by the terms of the contracts issued by that company or companies. The benefits of participants whose funds are invested in mutual funds or other similar investment products shall be limited to the value of the account.