[单选题]
Two point charges are separated by a distance r as shown.
The negative charge's acceleration is 3 times that of the positive charge.
What is the ratio $\frac{Gravitational force}{Electrostatic force}$ between the two point charges?
A. $\frac{Gm_1m_2}{30ke^2}$
B. $\frac{Gm_em_p}{ke^2}$
C. $\frac{Gm{_2}^2}{10ke^2}$
D. $\frac{Gm{_1}^2}{10ke^2}$
