The answer is a little tricky but it’s A
The most Senistive part of the chest
I think they describe a structure of cyclopentane. Cyclopentane is a highly flammable alicyclic hydrocarbon with a chemical formula C₅H₁₀, consisting of a ring of five carbon atoms each bonded to hydrogen atoms above and below the plane. It occurs as a colorless liquid with a petrol-like odor.
