There were no on-stage presenters, so there was only room for one Oscar on the stage pedestal. I'm sure you saw that huge shelf of Oscars off-stage in the wings. Multiple category winners were handed an Oscar when they left the stage before entering the press room.
This year's Best Actress race is one for the books. I have NO idea which of those five actresses is going to carry off the prize. Awards groups have split the prizes up with no clear favorite.