Which one is more reactive between alkane and alkene? Why?

(B) Alkene is more reactive than alkane.
This is because alkenes contain a carbon-carbon double bond $(C=C)$,which consists of one strong $\sigma$-bond and one weak $\pi$-bond.
The $\pi$-bond is electron-rich and easily accessible to electrophilic reagents,making alkenes susceptible to electrophilic addition reactions.
In contrast,alkanes contain only strong $\sigma$-bonds ($C-C$ and $C-H$),which are relatively inert and require high energy to break,making them less reactive.