[单项选择]

On Saturday August 12, 2000, during Northern Fleet training exercises in the Barents Sea, the Russian nuclear submarine Kursk sank in about 100 meters of water with some 118 sailors aboard. It’s known later that several officers were also aboard, observing the training exercises. The Kursk is lying on the ocean floor in the Barents Sea. The Russian Navy said that it was listing 30 degrees to port. Other sources reported it Was listing as much as 60 degrees. According to a Russian newspaper, when the submarine Kursk failed to make contact with the naval command at the right time later that day, Northern Fleet Commander Admiral Vyachesav Popov ordered rescue ships into the area. It took hours to find the submarine, as it didn’t launch a marking buoy before sinking.
Russian Navy Chief insisted that the submarine Kursk had been involved in a major collision, but a great deal of information shows that this is not true. Up till now, it’s believed that a
A. Because the Barents Sea is very icy and the weather is too cold.
B. Because Russia feared that the top secrets inside the Kursk will be let out.
C. Because Russian divers are much more skilled than those from Norway.
D. Because Russian government wants to bring the cost down to the lowest degree.