Answer
See explanation
Work Step by Step
Hydrocarbons having greater molecular weight have greater boiling point due to greater interaction of london dispersion force between molecules. In the same way, long chained hydrocarbons will have greater boiling point due to greater interaction of london dispersion forces between molecules than interaction in branched chain hydrocarbons.
First, the group of hydrocarbons will be arranged in the order of increasing molecular weight. The hydrocarbon having greater molecular weight will have greater boiling point.
Now, if two or more hydrocarbons have same molecular formula but different in structure i.e. the hydrocarbons are structural isomers to one another then we look at the molecular structure. Long chained hydrocarbons will have greater boiling point than that of branched chain hydrocarbons. For example, n-pentane and 2,2-dimethylpropane have the same molecular formula $C_{5}H_{12}$. Yet, n-pentane has the greater boiling point than 2,2-dimethylpropane because n-pentane is long chained hydrocarbon where as the other is a branched chain hydrocarbon.
Look at the below figure.
