Correct option is C
In welding, the electrode size is defined by the diameter of its core wire, which is the metal rod that conducts the welding current and melts to form the weld joint. The flux coating around the electrode provides shielding from atmospheric contamination but is not considered part of the electrode size.
The size of the core wire determines the current range and welding application. For example:
· 2.5 mm electrodes are used for thin materials.
· 3.15 mm and 4 mm electrodes are common for general-purpose welding.
· 5 mm and above are used for heavy structures.
