Question

under normal atmosphere pressure at earths surface, water molecules form a tetrahedral network stabilized by hydrogen bonds between adjacent molecules. extreme high - pressure, such as can be found in deep ocean waters, destabilizes these bonds and compresses waters structure, allowing water molecules within organisms to permeate proteins and impede crucial biological functions. yet deep - sea organisms known as piezophiles have adapted to extreme pressure. studies have found a positive correlation between the depths that various piezophiles inhabit and concentrations of a compound called trimethylamine n - oxide (tmao) in their muscle tissues, which has led a team of researchers to hypothesize that tmao reduces waters compressibility. which finding, if true, would most directly support the researchers hypothesis? a water molecules are found to be impervious to tmao even when the water molecules tetrahedral configuration has been distorted by high pressure. b examination of tmaos molecular structure shows that tmao molecules retain their shape even as pressure increases. c a positive correlation is found between concentrations of tmao and the rate at which waters molecular structure compresses as pressure increases. d analysis of waters molecular structure under high pressure reveals that hydrogen bonds are more stable when tmao is present than when it is not.

Explanation:

The researchers' hypothesis is that TMAO reduces water's compressibility. Option D supports this as it shows that hydrogen - bonds in water's molecular structure are more stable when TMAO is present under high pressure. Stable hydrogen - bonds would imply less compressibility. Option A is about water's imperviousness to TMAO, not its compressibility. Option B is about TMAO's shape stability, not water's compressibility. Option C shows a correlation that goes against the hypothesis (higher TMAO with more water compression).

Answer:

D. Analysis of water's molecular structure under high pressure reveals that hydrogen bonds are more stable when TMAO is present than when it is not.