Final answer:
The correct answer is A) London dispersion forces.London dispersion forces are the type of force absent when ions are absent and there is no polar or hydrogen bonding.
Step-by-step explanation:
The correct answer is A) London dispersion forces.
London dispersion forces, also known as van der Waals forces, are the weakest type of intermolecular forces. These forces occur between all molecules, whether polar or nonpolar. They are caused by temporary fluctuations in electron distribution that result in temporary dipoles in the molecules.
Unlike dipole-dipole forces, which require polar molecules, London dispersion forces can exist between nonpolar molecules as well. These forces increase with increasing molecular size, as larger molecules have more electrons to contribute to temporary dipoles.