Answer:
B. The Kievan state converted to Christianity.
Step-by-step explanation:
This was evident when initially around 979 AD, during the reign of Grand Prince Sviatoslav, his mother Olga was baptized and turned to Christian. Later in about 1000AD, Emperor Basil II and Grand Prince Vladimir of Keiv came to a warfare agreement which includes Grand Prince Vladimir converting to Christian.
Consequently, the Grand Prince who was widely known in modern time as a saint in the Orthodox Church was reported to use Christian Church to govern during his reign. He ultimately employed religion to rule and govern his subjects. From there on, the Kievan state cultured was freshly influenced by Christianity.