What term refers to nanomaterials used for drug delivery and dirt-repellent coatings?

• A. Nanotechnology
• B. Smart materials
• C. Advanced metal alloys
• D. Thermochromic Materials

Answer: (A)

This question tests recognizing nanotechnology as the field that covers nanoscale materials used in practical applications like medicine and protective surfaces. Nanomaterials enable drug delivery through nanoparticles that can carry and release drugs in a controlled way, improving targeting and reducing side effects. The same nanoscale engineering is used to create coatings that repel dirt by tuning surface roughness and chemistry, sometimes achieving water-repellent or anti-fouling properties. The other options describe different material concepts—smart materials focus on responsiveness to stimuli, advanced metal alloys are about metal mixtures and bulk properties, and thermochromic materials change color with temperature. So nanotechnology best fits nanomaterials used for both drug delivery and dirt-repellent coatings.