A 1mA beam of protons with a cross-sectional area of 0.5 sq. mm is moving with a velocity of \[3\times {{10}^{4}}m{{s}^{-1}}\]. Then charge density of beam is [CPMT 2002]

• A.            \[6.6\times {{10}^{-4}}C/{{m}^{3}}\]                             
• B.            \[6.6\times {{10}^{-5}}C/{{m}^{3}}\]
• C.            \[6.6\times {{10}^{-6}}C/{{m}^{3}}\]                             
• D.            None of these