Answer: Option (C) is the correct answer.
Step-by-step explanation:
An amphipathic molecules is defined as the molecule that contains both polar and non-polar parts.
For example, phospholipids are amphipathic molecules as they contain non-polar fatty acids known as tails and polar phosphate known as heads.
In amphipathic molecules, the polar water molecules tend to pull towards each other. As a result, non-polar parts tend to move away into the air.
Therefore, we can conclude that amphipathic molecules line up at a water surface because polar groups attract one another.