Select Multi-Answer Drop Down List

I have a Matrix Table, Profile, Drop Down List. Each list has unique categories, but I want a user to have the ability to select multiple answers. Any idea how to do this? I know I can do the Matrix Table, Profile, Multiple Answer, but some answers will have only 3 and others will have up to 8 options to choose from.
I like the Multiple Selection Box option, but I will have multiple categories that I want customers to review and I want them to all be within the same question.
I currently have this javascript to only show Scale Points if the option is not blank.

Qualtrics.SurveyEngine.addOnReady(function()
{
jQuery("#"+this.questionId+" select option:first-child").text("Select one");

jQuery("#"+ this.questionId + " option").each(function () {
if (jQuery(this).text().length < 2) {
jQuery(this).hide();
}
});


});