Respuesta :
The tendency of an element to loose an electron is called metallic property of that element.
1.Carbon has 4 valence electrons hence it's difficult to loose electrons.
2.Iodine has 7 valence electrons hence it will gain 1 electron and form octet.
3. Iridium has 2 valence electrons so it will loose electrons and gain stability.
4. Radon has 6 valence electrons hence difficult to loose electrons.
So Iridium is the correct answer.
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