Answer:
B. Single Replacement
Step-by-step explanation:
Single replacement:
It is the reaction in which one elements replace the other element in compound.
AB + C → AC + B
Chemical equation:
2HgO + Cl₂ → HgCl + O₂
This is the single replacement reaction. In this reaction chlorine replace the oxygen from mercury oxide and form mercury chloride.
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.
A + B → AB
Double replacement:
It is the reaction in which two compound exchange their ions and form new compounds.
AB + CD → AC +BD