Answer:
The correct option is 1. The area of cross section area is 48 mm².
Step-by-step explanation:
From the find it is noticed that the cross section is a rectangle with length 4 mm and width is 12 mm.
The area of a rectangle is the product of its dimensions.
![A=l\times w](https://tex.z-dn.net/?f=A%3Dl%5Ctimes%20w)
Where, l is length of the rectangle and w is width of the rectangle.
The area of cross section is
![A=4\times 12](https://tex.z-dn.net/?f=A%3D4%5Ctimes%2012)
![A=48](https://tex.z-dn.net/?f=A%3D48)
Therefore the area of cross section area is 48 mm². Option 1 is correct.