Final answer:
Hydrocarbons like cooking oil and gasoline are nonpolar, making them hydrophobic and not amphipathic, as they lack distinct polar regions to interact with both polar and nonpolar substances.
Step-by-step explanation:
The feature of cooking oil and gasoline (hydrocarbons) that identifies why the molecules are NOT amphipathic is A) Hydrophobic nature. Amphipathic molecules possess both hydrophilic (water-attracting) and hydrophobic (water-repelling) properties. Since hydrocarbons are largely nonpolar due to the close electronegativities of carbon (C) and hydrogen (H) atoms, they do not have distinct polar and nonpolar regions that would render them amphipathic. Consequently, hydrocarbons dissolve sparingly in water or other polar solvents. This lack of polarity means they cannot interact with both polar and nonpolar substances, which is a hallmark of amphipathic molecules.