Final answer:
A) Methane.
The molecule with the molecular formula CH4 is methane, which is the simplest alkane with one carbon atom and four hydrogen atoms.
Step-by-step explanation:
A molecule with the molecular formula CH4 is described as methane. Methane is the simplest alkane and consists of one carbon atom bonded to four hydrogen atoms, forming a tetrahedral structure. The molecular formula indicates the number of carbon and hydrogen atoms present in the molecule but does not provide information about its bonds or shape.
Alkanes follow the general formula CnH2n+2 and methane being the simplest, it fits this formula with n=1. Ethane, another alkane which is the next-largest after methane, has the molecular formula C2H6 indicating two carbon atoms each bonded to three hydrogen atoms.
Therefore, among the provided options A) Methane B) Ethanol C) Carbon dioxide D) Ethane, the correct answer for the molecular formula CH4 is A) Methane.