The correct option is C. In chemistry, a radical is defined as an atom, ion or molecule that possess an unpaired valence electron. Generally, radicals are highly reactive chemically. Examples of radicals are hydroxyl, hypochlorite, nitrate, carbonate, oxalate, permanganate, etc. Free radicals combine with one another or with single atoms to produce neutral substances. In the question given above, the two compounds given in option C have the same type of radical, which is hydroxyl radical.
Thymine has a methyl group and is better suited for the storage property of the DNA molecule as it is far more stable compared to Uracil. RNA contain Uracil instead of thymine so as to make differentiation of RNA molecule from DNA molecules easier.
The peripheral nervous system is made up of two systems; the somatic nervous system controls muscle movement and the autonomic nervous system connects with internal organs.
