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Verbal·Expression of Ideas·Rhetorical Synthesis

hard

While researching a topic, a student has taken the following notes:

• Soap forms as the result of a chemical reaction between fats and either sodium or potassium hydroxide.
• One end of a soap molecule is hydrophobic (water repelling), and one end is hydrophilic (water attracting).
• The hydrophobic ends of soap molecules adhere to hydrophobic surface contaminants, such as dirt and oils.
• The soap molecules form circular structures (micelles) around contaminants.
• The hydrophilic ends of the molecules encase the micelles in water, lifting the micelles and contaminants off surfaces.

The student wants to explain how soap removes a surface contaminant. Which choice most effectively uses relevant information from the notes to accomplish this goal?

A

Surface contaminants like dirt and oils are hydrophobic, not hydrophilic—meaning they repel water rather than attract it.

B

Micelles are circular structures created when soap molecules attach themselves to dirt or oils.

C

To remove dirt from a surface, soap molecules form a circular structure, or micelle, around the contaminant; next, the molecules encase the micelle in water, lifting it—and the dirt—off the surface.

D

Dirt, an example of a hydrophobic surface contaminant, can be removed from a surface by soap, which forms as the result of a chemical reaction between fats and either sodium or potassium hydroxide.