(A) - (II) precedence → "Take precedence over" is an idiomatic expression meaning to be more important than something else.
(B) - (III) wreak → "Wreak vengeance" is a common collocation meaning to inflict or cause revenge upon someone.
(C) - (IV) reign → "Reign" refers to the period during which a monarch or ruler holds power.
(D) - (I) savour → "Savour" means to enjoy or appreciate the taste and flavor of food.