Me i have to write an investigation question and hypothesis.
scenario: marissa is extremely curious 6th grader. during a snow days you notice the truck spreading salt all over the road. after the truck went away versus how she put on her snowbirds hat and gloves and went to the edge of her driveway made an observation. she made observation that the snow is new sink slowly. from her observation she is very eager to conduct investigation

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.