Consider the following statements in respect of the oxidizing flame due to excess of oxygen in welding:
1. At high temperature, it combines with many metals to form hard and brittle oxides.
2. It causes the weld bead and the surrounding area to have a scummy appearance.
3. It has good welding effect in welding of copper-base metal.
Which of the above statements are correct?
(a) 1, 2 and 3 (b) 1 and 2 only
(c) 1 and 3 only (d) 2 and 3 only