Choose the correct option.

1. Lake Baikal in Russia is one of its top ice diving
... . 2. It is truly an amazing place of natural beauty and ... . 3. The lake is host to 1550 species and ... of animals. 4. However, the attraction here is not the marine flora and fauna as many of it is very small or almost ... . 5. Divers come to Lake Baikal to see the beauty of the ice that covers the ... in winter. 6. They dive into one of the most ... experiences in their life.