Final answer:
The O-H bond, with an electronegativity difference of 1.4, is definitely polar covalent and is the most polar bond compared to the O-C bond because it exhibits greater electron imbalance between the oxygen and hydrogen atoms.
Step-by-step explanation:
To determine which covalent single bond is most polar among the options O-C and O-H, we need to consider the difference in electronegativities between the atoms forming the bond. A larger difference in electronegativities indicates a more polar bond, as the electrons will be more unequally shared, being drawn towards the more electronegative atom.
For the O-H bond, the electronegativity of oxygen is 3.5 and that of hydrogen is 2.1, yielding a difference of 3.5 - 2.1 = 1.4. Therefore, this bond will be definitely polar covalent, as it has a substantial difference, indicating a significant imbalance in electron sharing, making the O-H bond highly polar. On the other hand, the details for the O-C bond are not provided, but typically, the electronegativity of carbon is lower than that of oxygen, which means the O-C bond will also be polar; however, the difference is usually smaller than that of the O-H bond.
In conclusion, without the exact electronegativity for carbon provided, we must rely on a typical trend where the O-H bond has a higher electronegativity difference and is more polar compared to the O-C bond. Since the question specifically asks about these two bond types and given the information, the O-H bond is the most polar.