Use WGS84 Ellipsoidal Height as an Option?

[AlexLandherr]

I'm curious as to which altitude value is used for this application?

I've taken my glossary of terms from here: Elevation for beginners

Elevation types:

1. Ellipsoidal Height
2. Geoid Height
3. Orthometric Height

I am asking out of curiosity and as a clarification.

Maybe it could have a label of MSL for orthometric height and WGS84 for ellipsoidal height?