Which of the following questions could be answered through a scientific investigation? I. What type of antibacterial soap kills the most bacteria? II. What type of food do dogs think tastes the best? III. Does the color pattern of a butterfly affect its chance of survival? IV. Do cats feel sad when they are alone? A. II and III only B. I, II, III, and IV C. I and IV only D. I and III only

the correct answer would be d. hope this !

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.