Answer :
Submerged arc welding (SAW) is the welding process that uses a flux to protect the weld pool from atmospheric contamination, differentiating it from the other methods like Resistance welding, Electron beam welding, and GMAW. Therefore, the correct option is C.
The welding process that uses a flux to protect the weld pool is Submerged arc welding (SAW). In the SAW method, the weld area is covered by a blanket of granular flux, which, when melted, becomes conductive and provides a current path between the electrode and the work.
This process protects against atmospheric contamination by creating a shield around the weld zone. The other methods mentioned, such as Resistance welding, Electron beam welding, and Gas metal arc welding (GMAW), use different methods of protecting the weld zone or do not require flux.
