[单选题]
A parallel-plate capacitor is constrbv.k;;zuzwr e6 *edd*ucted with pla /u)piai6s.t(cw .unc te area of $0.40 \; m^{2}$ and a plate separation of 0.10 mm. How much energy is stored when it is charged to a potential difference of 12 V?
A. $2.5 \; mJ$
B. $5.0 \; mJ$
C. $7.5 \; mJ$
D. $10 \; mJ$