Given the task definition and input, reply with output. Given a scientific passage and an answer, generate a question for the given answer.

Passage: There are several types of radioactive decay, including alpha, beta, and gamma decay. In all three types, nuclei emit radiation, but the nature of the radiation differs. The Table below shows the radiation emitted in each type of decay. You can watch a video about the three types at this URL: http://www. youtube. com/watch?v=3koOwozY4oc . Answer: radiation
What is emitted by nuclei in alpha, beta, and gamma decay?