In allene (C3​H4​), the type(s) of hybridization of the carbon atoms is (are):

A

sp2 and sp

B

sp2 and sp3

C

sp and sp3

D

only sp2

Allene: H2​C=C=CH2​. The central carbon is attached to other carbons by two sigma and two pi bonds so it's hybridisation will be sp. The terminal carbon is attached to other carbon and hydrogen by 3 sigma and 2 pi bonds and hence, it's hybridisation will be sp²2.