First option.
The male tails are more attractive because of their long feathers , meanwhile the female tails are shorter than expected!
I think A. o2 is oxygen, h202 is a clear liquid like bleach, And H20 is water lol :P
I believe its the first one because manganese is mn and IV is 4 but the cross thing thing will making it the second one but then you have to simplify making it the first one i hope that helps:)
OPTION D IS YOUR ANSWER.............
The answer is A: biodegradable.
