Which is the strongest bond, ionic or covalent

An ionic bond  

Explanation:

There is some overlap, but an ionic bond is usually stronger.

The lattice energies of ionic substances have a range of 700 kJ·mol⁻¹ to 11000 kJ·mol⁻¹.

Covalent bond dissociation energies range from 150 kJ·mol⁻¹ to 1100 kJ·mol⁻¹.

i think it's letter a.

answermeridional ;