Adjust the width of multi select text to show all options

Is it possible to adjust the width of a multi select text field to display all the options contained therein? My goal is to enable the user to see all options listed so they don't accidentally chose an option that is close enough thinking the exact option is not available.

I'm trying to avoid if possible to individual check boxes for each option and then create a formula text field to concatenate all the check boxes that are checked. Thanks in advance.

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Ketki Ganpule
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