Answer :
The molecule that could diffuse across the plasma membrane is methane (CH4).
What is diffusion?
Diffusion is the movement of fluids or substances from regions of high concentration toward regions of lower concentration.
The plasma membrane is the semipermeable membrane that surrounds the cytoplasm of a cell. The semipermeability means that it allows some molecules through but blocks other substances.
The semipermeable plasma membrane readily allows the passage of small hydrophobic and polar molecules.
Therefore, the molecule that could diffuse across the plasma membrane is methane (CH4).
Learn more about semipermeability at: https://brainly.com/question/1652796
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