Answer:
(C)
Explanation:
The diagram is divided ninto 5 parts that is rectangles ABCD, CHGD, GFEH and triangles CIH and DGJ.
Area of rectangle ABCD=
![l{*}b](https://img.qammunity.org/2020/formulas/mathematics/middle-school/yhj0ynhtnuveem79w449d2p4srt0iz9bn4.png)
=
![12{*}6=72cm^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/498azbhyd3u107htgcgwoyf9lro1a3b18w.png)
Area rectangle CDHG=
![l{*}b](https://img.qammunity.org/2020/formulas/mathematics/middle-school/yhj0ynhtnuveem79w449d2p4srt0iz9bn4.png)
=
![12{*}8=96cm^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/cpah9w3yimkc05simsx0jpb1pjqfurmpil.png)
Area rectangle HGFE=
![l{*}b](https://img.qammunity.org/2020/formulas/mathematics/middle-school/yhj0ynhtnuveem79w449d2p4srt0iz9bn4.png)
=
![10{*}12=120cm^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/lzogztbc15ylyyjt1p7iqh7lmoxnxz1g7z.png)
Area of triangles CIH and DIG=
![2{*}(1)/(2){*}b{*}h](https://img.qammunity.org/2020/formulas/mathematics/middle-school/7s663if7emgtt02i7ekrgr2vlane89eq6o.png)
=
![6{*}8=48cm^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/lbmwdqw2ug65g3syu9jyssskykdx8xc86e.png)
Surface area of the triangular prism=Area of rectangle ABCD+Area rectangle CDHG+Area rectangle HGFE+Area of triangles CIH and DIG
=
![72+96+120+48=336cm^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/r7saojwh4uz6fs4hjrctye3a6oqy63iyjf.png)
Hence, option C is correct.