Answer: Covalent bond
Step-by-step explanation:
Water is a polar molecule and the structure of water molecules are held together by hydrogen bonding. The hydrogen atoms are attached to the oxygen molecules by covalent bond.
The electronegativity of hydrogen atom is different from oxygen molecules. Oxygen molecule has partial negative charge and hydrogen molecules has partial positive charge.
Due to this positive and negative charge the bond formed in hydrogen and oxygen molecule is covalent bond.