Instructions: Given a scientific passage and an answer, generate a question for the given answer.
Input: Passage: A nuclear fusion reaction is so named because the nuclei (center) of atoms fuse (join) together in the process. In stars like our Sun, hydrogen atoms join together to create a helium atom. Nuclear fusion reactions need a lot of energy to get started. Once they begin, they produce even more energy. ( Figure below ). Answer: helium atom
Output:
In stars like our sun, hydrogen atoms join together to create what?