Common link
Common link questions are pyramidal tossups which arrange clues about several distinct places, works, events, or entities to point to a common word or phrase describing all of them as the answer. They often add creativity to a question set or are used to incorporate important clues that would be too difficult as answer choices of their own. Individual common link questions have been criticized in the past for requiring the player to "read the writer's mind" or for having underspecific or overspecific answer lines; despite this, some number of common link questions are standard in good quizbowl sets.
Common links are not to be confused with tossups that simply list different things and expect the player to deduce a common attribute without any clues.
Example
From HSAPQ ACF-Format Set 1, Packet 3:
A 1998 work by Tracey Emin is entitled "My" one of these objects. One painting primarily set on one
of these objects depicts a woman, a ghastly demon, and a horse emerging from a curtain, and was
painted by Henry Fuseli. A large red one of these objects is found in Delacroix's Death of Sardanapalus,
and the right side of Jan Van Eyck's The Arnolfini Marriage also contains a red one of these objects. For
10 points, name this piece of furniture, on which the title figures of the paintings Olympia and Venus of
Urbino recline.
ANSWER: beds