Which of the following metals are obtained by electrolysis of their chlorides in molten state ?

(i) Na (ii) Ca (iii) Fe (iv) Cu

(a) (i) and (iv) (b) (iii) and (iv) (c) (i) and (iii) (d) (i) and (ii)

The correct option is d.
Na and Ca are obtained by electrolysis of their molten chlorides. These are very reactive metals. 
The oxides of very reactive metals cannot be reduced  with carbon. The highly reactive metals are extracted by the electrolytic reduction of their molten chloride. For example, sodium, magnesium and calcium are obtained by the electrolysis of their molten chlorides. The metals are deposited at the cathode (the negatively charged electrode), whereas, chlorine is liberated at the anode (the positively charged electrode).