. The insulation property of air breaks down at \[E=3\times {{10}^{6}}\] volt/metre. The maximum charge that can be given to a sphere of diameter \[5\,m\] is approximately (in coulombs) [MP PMT 1990]

• A.                    \[2\times {{10}^{-2}}\]
• B.                                      \[2\times {{10}^{-3}}\]
• C.                    \[2\times {{10}^{-4}}\]
• D.                                      \[2\times {{10}^{-5}}\]