Which of the following is not a functional isomer of hex–3–yne?
CH2=CH−CH2−CH2−CH=CH2
CH2=C=CH−CH2−CH2−CH3
CH2=CH−CH=CH−CH2−CH3
CH3-C≡C-CH2-CH2-CH3
Alkadienes are the functional isomers of Alkynes. 1, 2, 3 are functional group isomers of hex–3–yne.