A heavy hydrocarbon fraction obtained from the fractional distillation of crude oil is processed to meet industrial demand. Which row correctly describes the primary product obtained from the thermal cracking of this heavy fraction and its volatility?
Primary product of thermal crackingVolatilityABranched alkanesHighBBranched alkanesLowCAlkenesHighDAlkenesLow \begin{array}{|c|c|c|} \hline & \textbf{Primary product of thermal cracking} & \textbf{Volatility} \\ \hline \textbf{A} & \text{Branched alkanes} & \text{High} \\ \hline \textbf{B} & \text{Branched alkanes} & \text{Low} \\ \hline \textbf{C} & \text{Alkenes} & \text{High} \\ \hline \textbf{D} & \text{Alkenes} & \text{Low} \\ \hline \end{array} ABCDPrimary product of thermal crackingBranched alkanesBranched alkanesAlkenesAlkenesVolatilityHighLowHighLowRow A\textbf{A}A
Row B\textbf{B}B
Row C\textbf{C}C
Row D\textbf{D}D