The strength that causes unlike materials to adhere to each other.

• A. Adhesion
• B. Corrosion
• C. Solubility
• D. Flow

Answer: (A)

Adhesion is the force that causes unlike materials to stick together. It happens because of attractive forces between the molecules of different substances, such as glue bonding to paper or water clinging to glass. This differs from cohesion, which is the attraction between similar molecules within the same substance. The other terms describe different ideas: corrosion is a chemical degradation process, solubility is the ability of a substance to dissolve, and flow is the movement of a liquid. So adhesion best explains why dissimilar materials adhere.