( A ) Amongst isoelectronic species, greater the negative charge on the anion, large is the ionic radius
( B ) Atomic radius of the elements decreases as one moves across from left to right in then 2nd period of the periodic table
( C ) Atomic radius of the elements increases as one moves down the first group of the periodic table
( D ) Amongst isoelectronic species, smaller the positive charge on the cation, smaller is the ionic radius
