A ring of charge with radius 0.5 m has \[0.002\pi m\]gap. If the ring carries a charge of +1 C, the electric field at the center is

• A. \[7.5\times {{10}^{7}}N{{C}^{-1}}\]
• B.        \[7.2\times {{10}^{7}}N{{C}^{-1}}\]
• C. \[6.2\times {{10}^{7}}N{{C}^{-1}}\]
• D.        \[6.5\times {{10}^{7}}N{{C}^{-1}}\]