A metal ball B₁ (density 3.2 g/cc) is dropped in water, while another metal ball B₂ (density 6.0 g/cc) is dropped in a liquid of density 1.6 g/cc. If both the balls have the same diameter and attain the same terminal velocity, the ratio of viscosity of water to that of the liquid is
A 2.0
B 0.5
C 4.0
D Indeterminate due to insufficient data