Ekaterina "Katia" Alexandrovna Gordeeva (Russian: Екатерина Александровна Гордеева ) (born May 28, 1971) is a Russian (former Soviet) figure skater. Together with her partner and husband, the late Sergei Grinkov, she was the 1988 and 1994 Olympic Champion and four-time World Champion in pair skating. After Grinkov's death, Gordeeva continued performing as a singles skater. Using only the above description and what you know about the world, "Sergei Grinkov sang the Russian National Anthem at the opening ceremonies of the last olympics." is definitely correct, incorrect, or inconclusive? 