Statement I: Checking amphoteric nature of oxide pairs:
[SiO2,CO2]: Both acidic (non-metal oxides)
[SnO,SnO2]: Both amphoteric
[PbO,PbO2]: PbO is amphoteric but PbO2 is predominantly acidic/oxidizing
[GeO,GeO2]: Both amphoteric (Ge is metalloid)
2 pairs have both oxides amphoteric. Statement I is true.
Statement II: BF3 has B with 6 valence electrons (electron deficient), acts as Lewis acid, forms BF3⋅NH3 adduct, has sp2 hybridization giving trigonal planar geometry. Statement II is true.