Disable option in multiple select. Needs fix or improvements.

[chi...@amuratech.com]

Use case:
I'm using multiple-select for displaying tags ["A", "B", "C"]. In which I want option "A" to be disabled. I tried appending option disabled="disabled" to the option which disables the option.
That is not what I want to do. I want to remove 'x' (close mark) from the input area. So no user will be able to remove it.