What is name of astronaut who spends the most time in space ever?

A. Bilk Nancy

B. Olegeo Naci

C. Oleg Kononenko

D. Lols Pansu

Brief Facts about Oleg Kononenko:

Oleg Kononenko is a Russian cosmonaut who has spent most time in space. He has spent almost 878 days and 12 hours in Earth space which is a new world record in space history. This is equal to two-and-a-half years according to the report published by Sky News.