Select the correct answer for each of the following questions. Each question has only one correct answer.
a) Which of the following elements has the largest atomic radius? 
      Li              K              O                S
 
b) Which of the following elements has the highest value of first ionization energy?
      Li              K              O                S
 
c) Which of the following elements has the greatest metallic character?
      Li              K              O                S
 
d) Which of the following ions has the largest radius? 
      Li⁺            K⁺             O^2-            S^2-
 
e) Which of the following is the most electronegative element?
      Ba              Ca               S             Te