In a scenario where a chemist aims to produce a polymer with a specific architecture using living polymerization, which of the following initiation methods would be most suitable if they also want to utilize the unique properties of light for activation?

The most suitable initiation method is photoinitiation, where a light‑absorbing initiator or catalyst is activated by photons to generate the active species needed for living polymerization. Light provides precise spatial and temporal control, allowing the chemist to turn polymerization on and off or to pattern the material. For example, using a photo‑ATRP system, blue light excites a transition‑metal complex that transfers an electron to the dormant chain ends, creating radicals that propagate while keeping the chain ends capped. This approach keeps the polymer chains living, lets the chemist tune the reaction with light intensity, and exploits light’s unique ability to deliver energy without heating the bulk solution.