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]: arabesque is an artistic decoration.
[A]: arabesque


[Q]: molar mass is the mass of a substance that has 6.022 × 10 atoms (avogadro's number).
[A]: molar mass


[Q]: s/2003 j 12 is a moon of jupiter, and is the smallest known.
[A]:
s/2003 j 12