Support grouping answers under "other"

[ShacharHarshuv]

Suppose you want to make an exercise with a large range of options, but you want to only answer whether the answer is X, Y or "other". This can be a good way to make an exercise easier.

Example: play a chord progression with all diatonic chords, but the user need only to choose between I, IV, V or "other" (any other chord in the key).

This can be farther expanded to specifying specific groups. For example: "tonic" (I or vi") "subdominant" (ii or IV), "dominant" (V or vii). This can be extremely useful when adding more options and can make the exercises super configurable.

This is an advance feature though and need to be though thoroughly in term of UX etc.