You may have been thrown off by "seated". Make the sentence "They are all there and _______ for your speech to begin" and how do you fill the blank?
"Seated" is a little bit complicated. We have the verb "to sit" which is usually intransitive (does not take an object); e.g., Please sit (down). We also have the verb "seat" which is transitive (requires an object); e.g., The host