Which defect types are commonly associated with GTAW, and how can they be mitigated?

• A. Cracking due to hydrogen.
• B. Porosity only.
• C. Porosity, lack of fusion, undercut, crater cracks; mitigate by cleaning, drying electrodes, shielding gas flow, current and travel speed, and joint fit-up.
• D. Excessive oxide layer.

Answer: (C)