What is the hybridization of H2O?

See explanation.
To do the hybridization of ##”H”_2″O”##, we look for the central atom in the molecule. The central atom is oxygen, so we do the hybridization with respect to oxygen.
Oxygen contains 2 lone pairs of electrons + 2 with the hydrogen atoms, therefore it uses 4 hybrid orbitals.
When these 4 orbitals are formed, they form from the ##2 s## and ##2p## orbitals. So water shows ##”sp”^3## hybridization.