State the temperature and pressure in the following reaction:$nCH_2=CH_2(Ethylene)\rightarrow -(CH_2-CH_2-)_n(polyethylene)$

Question

$\begin{array}{1 1}(a)\;350-570K,1-2atm\\(b)\; 300-400K,1-2atm\\(c)\;350-570K,1000-2000atm\\(d)\;300-400K,1000-2000atm\end{array}$