If oxygen which has an electronegativity of 3.5 bonds with hydrogen which has an electronegativity of 2.1 the bond between the two atoms will be classified as a polar what bond?

The bond between oxygen and hydrogen will be classified as polar covalent. This is because the electronegativity difference between the two atoms (3.5 - 2.1 = 1.4) is significant enough to create an uneven distribution of electrons, resulting in a partial negative charge on oxygen and a partial positive charge on hydrogen.