Answer:
Polarity.
Explanation:
The most important intermolecular force to allow a solvent to dissolve in water is polarity. This is because water is a polar substance and there is a chemical law that states that there is only solubility between substances of equal polarity. Thus, water is only able to dissolve a polar substance, just like it. In this case, we can say that the equal polarity between the two solvents is the most important for one to be able to dissolve the other.