It's a 1x2x3 box, aka parallelepiped. So we have 2 1x2 faces, 2 2x3 faces and 2 1x3 faces. We add them up:
A = 2(1 × 2 + 2 × 3 + 1 × 3) = 2(2+6+3) = 22
Answer: d. 22