A solid sphere of radius R made of a material of bulk modulus K is surrounded by a liquid in a cylindrical container. A massless pistion of area A floats on the surface of the liquid. When a mass M is placed on the piston to compress the liquid the fractional change in the radius of the sphere, `deltaR//R`, is .............
A. `(mg)/(Ka)`
B. `(Ka)/(mg)`
C. `(Ka)/(3mg)`
D. `(mg)/(3Ka)`