Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.

[Q]: tactopods are members of a proposed clade of ecdysozoans called tactopoda.
[A]: tactopoda


[Q]: ligny-sur-canche is a commune.
[A]: ligny-sur-canche


[Q]: firefighters or firemen are people whose job is to put out fires and rescue people.
[A]:
firefighter