Answer variants:
The reaction of sodium hydroxide with hydrochloric acid is a double displacement reaction.
Metathesis reaction is another name for a single displacement reaction.
\(2Na_{(s)}+Cl_{2(g)}→2NaCl_{(s)}\)

This reaction is an "Element+Element → Compound" type reaction.
\(2NaOH+CuSO_4→Cu(OH)_2+Na_2SO_4\)

This is an example of a double displacement reaction.
 
Incorrect statement: