The atomic radius of main group elements generally increases down a group because as there are more electrons they are farther away from the nucleus and the electrons closer to the nucleus shield the outer electrons from the protons for attraction.
Here we go, this is from an essay I once wrote, hope it helps.
Answer:
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Explanation:
Answer:
The specie which is oxidized is:- 
The specie which is reduced is:- 
Explanation:
Oxidation reaction is defined as the chemical reaction in which an atom looses its electrons. The oxidation number of the atom gets increased during this reaction.
Reduction reaction is defined as the chemical reaction in which an atom gains electrons. The oxidation number of the atom gets reduced during this reaction.
For the given chemical reaction:
The half cell reactions for the above reaction follows:
Oxidation half reaction: 
Reduction half reaction: 
Thus, the specie which is oxidized is:- 
The specie which is reduced is:- 
It's B ------------------------------------