A \(+7.5 \mathrm{nC}\) point charge and a \(-2.0 \mathrm{nC}\) point charge are \(3.0 \mathrm{~cm}\) apart. What is the electric field strength at the midpoint between the two charges?

A. \(3.3 \times 10^{3} \mathrm{~N} / \mathrm{C}\)

B. \(5.7 \times 10^{3} \mathrm{~N} / \mathrm{C}\)

C. \(2.2 \times 10^{5} \mathrm{~N} / \mathrm{C}\)

D. \(3.8 \times 10^{5} \mathrm{~N} / \mathrm{C}\)