Potential Energy of Point-Charges: Consider the Group of Three+2

Potential energy of point-charges: Consider the group of three+2.4 nC point charges shown in the figure. What is the electric potential energy of this system of charges relative to infinity? (k = 1/4πε₀ = 8.99 × 10⁹ N ∙ m²/C²)

A) 4.1 × 10^-6 J
B) 4.6 × 10^-6 J
C) 4.2 × 10^-6 J
D) 4.4 × 10^-6 J