Creating feature-linked annotation as either single-part or multi-part

Question

I have two feature-linked annotation features in a geodatabase. Both appear to be identical in every way, except that one creates annotations as single-part and the other creates them as multi-part. I know I could convert one to the other, but I'm looking for an option to create a new annotation feature as either single-part or multi-part. If there is no such option, how does ArcMap decide to which to create an annotation as?

Answer 1

In the label expression for my annotation feature, checking the 'Remove extra spaces from label' box in the 'Maplex' tab of the label expression makes the annotation be created as single-part. If the box is unchecked it is created as multiple-parts.