High Voltage DC (HVDC) transmission is mainly used for

Choose two appropriate auxiliary components of a HVDC transmission system from the following
$$1.$$ D.C. line inductor
$$2.$$ A.C. line inductor
$$3.$$ Reactive power sources
$$4.$$ Distance relays on D.C. line
$$5.$$ Series capacitance of A.C. line

Out of the considerations (i) to (iv) listed below,
(i) No distance limitation related to steady state stability
(ii) No reactive power requirement from the system at the two terminals
(iii) No substantial effect on fault level of the two systems at the terminals inspite of the inter connection
(iv) no corona problems
The considerations which constitute advantages of HVDC transmission are

Bulk power transmission over long HVDC lines are preferred, on account of