The correct option is D) both A and B. In fact, the strength of an electric field produced by a single point charge is given by
[tex]E=k \frac{Q}{r^2} [/tex]
where Q is the charge that generates the field, k is the Coulomb's constante and r is the distance from the charge source of the field.
From the equation, we see that the strength of the field depends on A) the amount of charge that produced the field (Q) and B) the distance from the charge (r), so the correct option is D.
