6. The reaction
A decomposition
Cu + 2AgNO3 → Cu(NO3)2 + 2Ag, is an example of a ?
B single displacement
synthesis D
double displacement

B) single displacement

Explanation:

The given reaction is single displacement reaction.

Cu + 2AgNO₃  →  Cu(NO₃)₂ + 2Ag

Copper displace the silver and react with nitrate to form copper nitrate.

Single replacement:

It is the reaction in which one elements replace the other element in compound.

AB + C → AC + B

While other options are incorrect because,

Decomposition reaction:

It is the reaction in which one reactant is break down into two or more product.

AB → A + B

Synthesis reaction:

It is the reaction in which two or more simple substance react to give one or more complex product.

Double replacement:

It is the reaction in which two compound exchange their ions and form new compounds.

AB + CD → AC +BD

it is the most commonly accepted one