Analyze the relationship between 'was' and 'HarperCollins' within the context of the input sentence.
Options: chief executive officer, owner of, publisher, founded by

At book publishing, HarperCollins had a strong quarter with revenues down only 3% to $407 million and segment EBITDA up 9% to $47 million despite significant bricks-and-mortar store closures, which was a far better performance than we had anticipated.
publisher