No reason you couldn't have answers 3 and 4.
AFAIK the question is specifically about what ASE 15 can resolve with hashing and that would be 1 and 2.
Whilst a having clause could maybe be satisfied with hashing (in other RDBMS), that would only be possible if the input into the having clause was something that needed to be filtered or sorted in some way (hash or otherwise). Perhaps if there were some way of generating a complex plan which optimistically applied the having before the grouping then there could be some scope to experiment with another hashing operator.
In ASE what makes it to the having clause is something that is simply filtered by the search argument of the having clause after the grouping has taken place.
