The correct option is B 6:π
Let the radius of the sphere which fits exactly into the cube be r units. Then, length of each edge of the cube=2r units.
Let V1 and V2 be the volume of the cube and sphere respectively.
Then,
V1=(2r)3 and V2=43πr3
∴V1V2=8r343πr3=6π⇒V1:V2=6:π.