Genetic variation is the answer to ur question
I believe its the very last one or the very 1st one. sorry I could only give a 50/50 answer:/
Elements [or radicals] with valency one are monovalent, those with valency two are divalent, and those with valency three are trivalent.
...
What is the Valency of an Element / Radical?
Valency Divalent [2]
Element / Radical Oxide [Oxygen]
Symbol O
Ion O2-
Answer: I believe the answer is D: a large body of water.
i hope this helps sorry if it doesnt ;-;
love your pfp btw :D