The correct options are
B For almost three months from May to July, the sun never sets.
D Due to the relatively warm weather, some of the ice melts.
The summer in the Tundra sees higher temperatures than the winters, but is still cold. There is a melting of the frost and frozen water bodies. There is a growth of new vegetation. Sunlight is slowly received by this region where during May, June, and July the sun does not set.