Answer: Option (b) is the correct answer.
Explanation:
More is the electronegativity of an atom or element more will be its reactivity.
When we move across a period from left to right in a Periodic table then there will increase in electronegativity. And, when we move down a group then there will be decrease in electronegativity.
Oxygen, sulfur and selenium are all group 16 elements. So, their electronegativity decreases down the group. Also, nitrogen is less electronegative than oxygen atom.
Hence, we can conclude that out of the given options element oxygen is more reactive than the others.
