Concept:Combustion is the only reaction that every hydrocarbon undergoes when burnt in sufficient oxygen.
Explanation:A hydrocarbon contains only carbon and hydrogen.
When it burns completely in excess oxygen, it always produces carbon dioxide and water.
For example, the general combustion equation is:
Hydrocarbon+O2→CO2+H2OThis holds true for alkanes, alkenes, alkynes, and aromatic hydrocarbons alike.
Addition reactions occur mainly in unsaturated hydrocarbons like alkenes and alkynes, not in all hydrocarbons.
Polymerization requires specific monomers with double bonds or reactive sites, so it is not common to all hydrocarbons.
Condensation is a reaction typical of functional groups like alcohols or acids, which hydrocarbons lack.
Hence, only combustion is common to all hydrocarbons.
Answer:A. Combustion