H2Ohassp3 hybridisation and angular shape due to 2 lone pair of electrons.
NH3hassp3 hybridised nitrogen atom and pyramidal shape due to 1 lone pair of electrons.
SiO2hassp3hybridised atoms, it is a network solid and the shape is tetrahedral around each silicon atom.
SO2hassp2 hybridised sulphur atom and the shape is V-shaped due to 1 lone pair of electrons.
BF3hassp2 hybridised boron atom and the shape is trigonal planar.
BeCl2→sp
CO2→sp
CH4→sp3
Hence the answer is 4