Answer:
Every oxidation must be accompanied by a reduction.
Explanation:
Oxidation and reduction are complementary processes. There can be no oxidation without reduction and vice versa. It is actually a given an take affair. A specie looses electrons which must be gained by another specie to complete the process. This explains why the selected option is the correct one.
Even though Hydrogen is originally in group 1, based on this property, we can say it is in group 6.
Because:
Group 6 would mean that it only needs 2 more valence electrons till the octet (8 valence electrons). This would make it reactive, yet, in normal conditions, unlike group 7.
I hope this help crystal lattic