In liquid ethanol, CH₃CH₂OH Which intermolecular forces are present? A) Dispersion, hydrogen bonding and dipole-dipole forces are present. B) Only dipole-dipole and ion-dipole forces are present. C) Only dispersion and dipole-dipole forces are present. D) Only hydrogen bonding forces are present.

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Ethanol (CH3CH2OH) has a polar covalent bond due to the difference in electronegativity between carbon, hydrogen, and oxygen atoms. The presence of polar bonds leads to dipole-dipole force that is significant in liquids with polar molecules. 
Moreover, Ethanol has an -OH (hydroxyl) functional group, which makes it possible for hydrogen bonding with other ethanol molecules. Hydrogen bonding is a strong type of dipole-dipole force that exists between polar molecules containing hydrogen atoms bonded to electronegative atoms (like nitrogen, oxygen or fluorine). 
Finally, Dispersion force takes place amongst all molecules, but if they are filled with a polar group or a low boiling point, dispersion force can be negligible. Ethanol has a relatively low-boiling-point substance that leads to a strong dispersion force.

In Liquid Ethanol, CH3CH2OH

In Liquid Ethanol, CH₃CH₂OH