The correct option is D It is a polar molecule
The C atom undergoes sp hybridisation. Two sp hybridised orbitals of carbon atom overlap with two p orbitals of oxygen to make two sigma bonds.
Other two electrons are involved in pπ - pπ bonding with oxygen atom.
CO2 is a linear molecule and the oxygen atoms on each end are symmetrical. Polarity results from an unequal sharing of valence electrons. Because of this symmetry, there is no region of unequal sharing and thus, CO2 is a non polar molecule. Hence, the correct answer is option (d).