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.

Input: Consider Input: zirconium is a chemical elemental metal.

Output: zirconium


Input: Consider Input: the sun belt conference is a group of college sports teams that play each other on the ncaa division i level.

Output: sun belt conference


Input: Consider Input: børre knudsen (september 24, 1937 – august 17, 2014) was a norwegian lutheran minister.


Output: børre knudsen