The correct answer is A. CaF2.
The covalent character of a compound is determined by the difference in electronegativity between the atoms in the compound. The higher the difference in electronegativity, the more covalent the compound.
In CaF2, the electronegativity of calcium is 1.00 and the electronegativity of fluorine is 4.00. The difference in electronegativity is 3.00, which is the highest of the four compounds. Therefore, CaF2 has the highest covalent character.
In CaCl2, the electronegativity of calcium is 1.00 and the electronegativity of chlorine is
64 288 64 288 64S117.2 64 74.6 75.5c-23.5 6.3-42 24.9-48.3 48.6-11.4 42.9-11.4 132.3-11.4 132.3s0 89.4 11.4 132.3c6.3 23.7 24.8 41.5 48.3 47.8C117.2 448 288 448 288 448s170.8 0 213.4-11.5c23.5-6.3 42-24.2 48.3-47.8 11.4-42.9 11.4-132.3 11.4-132.3s0-89.4-11.4-132.3zm-317.5 213.5V175.2l142.7 81.2-142.7 81.2z"/> Subscribe on YouTube