Answer:
Answer choise D => Be - Cl
Explanation:
A quick way to define whether or not a bond is ionic or covalent is to look at the positions of the elements on the periodic table. The elements that have the greater positional distance between them will be the more ionic and the elements that are close together will be more covalent.
The positional distance between Be and Cl is greater than any of the other choses and therefore more ionic in nature.
