Consider the following statements for an induction furnace:
(i) High-frequency current is generally used for the furnace working.
(ii) There is less loss of alloying elements due to oxidation.
(iii) Pronounced stirring action of molten metal occurs inside the furnace.
(iv) Slag cover is essential for the efficient working of the furnace.
Which of the above statements are correct?
(a) 1, 3 and 4 only (b) 2, 3 and 4 only
(c) 1, 2 and 3 only (d) 1, 2,3 and 4