the reactant Zinc and HCl indicate the single displacement because
zinc metal displaces hydrogen from HCl to form hydrogen gas and zinc chloride.
Step-by-step explanation
A single displacement reaction is type of reaction in which element react with compound and take the place of another element in that compound.
When Zn react with HCl , Zn (an element) displaces H from Hcl (compound) to H₂ gas and ZnCl₂ according to equation below
Zn +2 HCl→ znCl₂ +H₂