In reaction $R$, numerous molecules of $J$ combine to produce a long-chain molecule called $K$. $K$ is the sole product. Which row gives the correct description of molecule $J$, reaction $R$ and molecule $K$?
- Amolecule $J$: polymer; reaction $R$: addition; molecule $K$: monomer
- Bmolecule $J$: monomer; reaction $R$: addition; molecule $K$: polymer
- Cmolecule $J$: polymer; reaction $R$: cracking; molecule $K$: monomer
- Dmolecule $J$: monomer; reaction $R$: cracking; molecule $K$: polymer