The amount of work done in blowing a soap bubble such that its diameter increases from d to D is (T=surface tension of the solution)

Options

A. `4pi(D^(2)-d^(2))T`
B. `8pi(D^(2)-d^(2))T`
C. `pi(D^(2)-d^(2))T`
D. `2pi(D^(2)-d^(2))T`

Answer

D