Alcohol Phenols And Ethers

$$\begin{aligned} & \mathrm{CH}_3-\mathrm{CH}=\mathrm{CH}-\mathrm{CH}_2 \mathrm{OH} \stackrel{\mathrm{PCC}}{\longrightarrow} \\\\ & \mathrm{CH}_3-\mathrm{CH}=\mathrm{CH}-\mathrm{CHO} \end{aligned}$$

Hybridisation change involved at \(\mathrm{C}\)-\(1\) in the above reaction.