Answer : 4. "Peggy Whitson"
Explanation :

Answer: D) Peggy Whitson Explanation: Peggy Whitson on 24 April 2017 broke the record for most days spent in space (cumulatively) by a US astronaut. She broke the previous record set by Jeff Williams who had spent a total of 534 days in space. – Whitson has been currently living and working aboard the International Space Station (ISS), for which she was launched in November 2016 using a Russian Soyuz capsule. At the time of her launch, she had already accumulated 377 total days in space. – Her mission was recently extended for an additional three months. Now when she will return from ISS in September 2017, she would have accumulated more than 600 days in space.