Among the options provided, the correct answer is c) methane (CH4).
Organic molecules are generally defined as compounds that contain carbon atoms bonded to hydrogen atoms, and may also include other elements like nitrogen, oxygen, sulfur, and phosphorus. In this case:
- a) Carbon dioxide (CO2) – Although it contains carbon, it lacks hydrogen and is classified as an inorganic molecule.
- b) Water (H2O) – This molecule does not contain carbon, and is therefore inorganic.
- c) Methane (CH4) – This is a classic example of an organic molecule. It consists of one carbon atom bonded to four hydrogen atoms.
- d) Hydrochloric acid (HCl) – This compound has hydrogen and chlorine, but does not contain carbon, making it inorganic.
- e) More than one of these is an organic molecule – This is incorrect since only methane qualifies as organic.
Thus, the choice that best fits the definition of an organic molecule is methane (CH4).