In this task, you're given an open-domain question. Your task is to provide an answer to the given question. There is only one unique answer for each question. Your answer should be short, and refer to an entity, date, number, etc. Do not put your answer in the context of a sentence.

What is on top of the space needle?
observation deck

Who is the boy in rihanna's we found love video?
Dudley O'Shaughnessy

Who plays carl's mom in the walking dead?

Sarah Wayne Callies