Which one of the following is a double-displacement reaction?
~there can be more then one answer~

a. 2h2 (g) + o2 (g) → 2h2o (g)
b. 2h2o (l) → 2h2 (g) + o2 (g)
c. naoh (aq) + hcl (aq) → nacl (aq) + hoh (l)
d. cu (s) + 2agno3 (aq) → cu(no3)2 (aq) + 2ag (s)

c

Explanation: Na displaced H and Cl displaced OH in the chemical equation

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