Correct answer is option C.

• Cold shut is also known as lap or fold. A defect such as lap that forms whenever metal folds over itself during forging.
• Earing is one of the major defects observed during deep drawing process due to anisotropic nature of sheet metal. Earing is defined as formation of waviness on uppermost portion of deep drawn cup.
• Alligatoring is the defect, usually occurs in the rolling of slabs (particularly aluminium and alloys). In this defect, the work piece splits along a horizontal plane on exit, with the top and bottom.
• Shrinkage porosity is caused by the absorption of nitrogen, oxygen and hydrogen in the molten weld pool which is then released on solidification to become trapped in the weld metal.