Answer:
Christina Koch spent time at the South Pole and Chris Hadfield spent time at the bottom of the ocean.
Step-by-step explanation:
In this question, we are told that astronauts spend time training for prolonged isolation in space. If we want to find evidence of this claim in the text, we need to look for examples that support this claim. Virtual communication, races, social distancing or journaling have very little to do with being able to tolerate extreme isolation for a long period of time. However, spending time at the South Pole or at the bottom of the ocean are great ways to experience extreme isolation.