the answer is d, cuz i just did it rn on my study island and i got it right :)
Chem bonds by exchanged charges create new characteristics as a result
Answer:
the ionic radius of the anion 
Explanation:
From the diagram shown below :
The anion
is located at the corners
The cation
is located at the body center
The Body diagonal length = 
∴ 
Given that :
(i.e the ratio of the ionic radius of the cation to the ionic radius of
the anion )

Also ; a = 664 pm
Then :

Therefore, the ionic radius of the anion 