If a store room of a house is in the shape of a cuboid having a length of 3 m, a width of 2 m, and a height of 4m, find the total area of its four walls.

A

50 $$m^{2}$$

B

20 $$m^{2}$$

C

40 $$m^{2}$$

D

24 $$m^{2}$$