<span>Comparative embryology is the study which determines the organisms that have the same and almost identical embryo development.
---
While, comparative morphology is the scientific study of organisms where their structures, physical entities and elements are identified to be similar or dissimilar. Using only simple basis of empirical observation, a scientist can detect whether two animals are of the same family or not.</span>
UV rays reacting with the O2 molecules
I might be wrong a little but
Hope the helps :)
Answer:
D, but if feel sorry my second guess will be B
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.