The correct option is
D acetone
Acetylene reacts with
Hg+2/H2SO4 to form acetaldehyde (B).
Then acetaldehyde reacts with CH3MgX/H2O to form 2-propanol (C), which undergoes oxidation to form acetone (D).
CH≡CHHg+2/H2SO4−−−−−−−−→CH3CHOCH3MgX−−−−−−→CH3CH(OH)CH3(O)−−→CH3COCH3
So final product D is Acetone.