This selection is mainly about how scientists are
A engineering ships that can more easily move through the water.
B designing surfaces to help more birds develop water repellent coats.
C learning from plants and animals to create materials that repel the cold.
D solving many problems by creating surfaces that repel all sorts of liquids.
The correct answer is D: solving many problems by creating surfaces that repel all sorts of liquids.
Explanation: The selection focuses on the innovative ways scientists are developing materials that can repel various liquids, which can lead to solutions for different practical challenges. This theme indicates a broader application of their research in creating versatile, repelling surfaces.