In which of the following compounds carbon atom undergoes hybridization of more than one type(i) CH3CH2CH2CH3(ii) CH3−CH=CH−CH3(iii) CH2=CH−CH2−CH3(iv) H−C≡C−H

In (ii) CH3−CH=CH−CH3, the carbon atoms C1  and  C4  are  sp3 hybridized while C2  and  C3  are  sp2 hybridized.In (iii) CH21=CH2−CH23−CH34, the carbon atoms C1  and  C3  are in sp2  while  C3  and  C4  are  in  sp3 state of hybridizationIn (i) all the carbon atoms are sp3 hybridized while in (iv) both carbon atoms are in sp state of hybridization.