What kinds of bond breakage and bond formation take place in the addition polymerisation of alkenes?
- Abond breakage: $\pi$ only; bond formation: $\sigma$ only
- Bbond breakage: $\pi$ only; bond formation: $\sigma$ and $\pi$
- Cbond breakage: $\sigma$ and $\pi$; bond formation: $\sigma$ only
- Dbond breakage: $\sigma$ and $\pi$; bond formation: $\sigma$ and $\pi$