Learn English – “Is” vs. “Are” when using (s)

Although the pattern of writing a word like option(s) is called paranthetic plurals, the word is both singular and plural.

If the usage of the word in the sentence is extremely limited (like in the example you provided) you can use it like

Regardless of what option(s) is (are) decided

If the usage becomes more complex, it's better to stick with one of the forms throughout. Although in some cases, like a legal document, where precision is of utmost importance, you need to mention both the forms either through option(s) style or option \ options style.

From Chicago Manual of Style :

A term ending in “(s)” is both plural and singular. If you must use such a device (and it can be a useful shorthand), you have to be prepared to adjust the surrounding context as necessary: for example, “the award(s) is (are) accounted for.” A parenthetical plural verb must correspond to the parenthetical ending. But that’s an awkward example. In general, avoid such shorthand unless it can be used simply and effectively, as in the following example:

Place an “about the author(s)” statement on the copyright page (usually page iv).