I'm looking for a term to describe a set of which at most one element can be selected.
Example
We have the set {0,1,2}. As shown earlier, this is a [insert word here], so we have to select at most one element.
The reason for this is that in the same paper, there is also another type of set (of which at least one has to be selected). Therefore, I need to give both these sets a name. For the latter, I'm thinking of something like 'non-empty selection set'. For the former, I don't have a clue.