Which term best describes this reaction?

condensation polymerization
addition polymerization
hydrohalogenation
hydration

The best term that describes the reaction is addition polymerization

Explanation:

Polymerization is a process which small molecules, monomers, undergo a chemical reaction to form polymer chains. The two general types are: addition polymerization and condensation polymerization.

Addition polymerization occurs when monomers reacts by the opening of the double bond to form a long carbon chain. The reaction continues until the reactive intermediate is destroyed in a termination reaction. This is a major process of producing polymers such as: poly(ethene) and poly(propene). It process has three stages which are: initiation, propagation, and termination.