Association of molecules in water is due to:

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the reason behind the association of molecules in water. Here, we need to identify the type of bonding that leads to this association.

2. **Identifying the Type of Bonding**: The association of water molecules occurs due to intermolecular forces. Specifically, we are looking for the type of intermolecular bonding present in water.

3. **Defining Hydrogen Bonding**: Hydrogen bonding is a specific type of intermolecular force that occurs when a hydrogen atom covalently bonded to a highly electronegative atom (like oxygen) is attracted to another electronegative atom. In water (H₂O), each water molecule can form hydrogen bonds with neighboring water molecules.

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