The parent chain of the following hydrocarbon is
Hexane
Octane
Dodecane
Nonane
Longest chain is as shown above
Number of carbon = 8 ⇒ (b) Octane
Nonane is a hydrocarbon which is isomeric with 2-methyl-3-ethyl hexane.
Structural isomers of octane,nonane,decane.with names