for qn 2, what about C-C bond forming head on with p-orbital
since its hybridised?
C-C sigma bonds are either sp-sp, sp-sp2, sp-sp3, sp2-sp, sp3-sp,
sp2-sp2, sp3-sp2, sp2-sp3, or sp3-sp3.
If you interpret the question to include p orbitals as part of
hybridized orbitals, then yes, B would be the answer. If you
interpret it to mean unhybridized orbitals only, then D would be
the answer. In the context of hydrocarbons at least.