Only two of the chairs matched the table.
the other options all have one thing in common, they are of course, incomplete sentences, starting in the middle of a sentence or at the end. 'After Chris finished the chemistry experiment' would most likely be at the end of a sentence, because it is missing a comma after the word after. It would be complete if it were to have a comma. 'Never had any interesting activities' is incomplete as well, for we don't know who or what never had any interesting activities, therefore one cannot simply start off a sentence like this. It would be complete if there were a given name, like 'Robert never had any interesting activities'. 'Almost all the swimmers following the rules' is also incomplete because it simlly doesn't make sense! The world Following makes the sentence confusing, we would need to change it to Almost all the swimmers FOLLOWED the rules, to make sense. Hope this helps ~♡