Which term refers to materials that combine multiple substances to create a material with enhanced properties?

• A. Micro encapsulation
• B. Composite materials
• C. Thermochromic ink
• D. QTC

Answer: (B)

Combining two or more substances to create a material with enhanced properties is described by composite materials. In composites, a reinforcement (like fibers or particles) is embedded in a matrix (such as a polymer or cement). The reinforcement provides strength and stiffness, while the matrix holds everything together and transfers stress, so the final material can be stronger, tougher, or lighter than its individual parts. Classic examples include fiberglass (glass fibers in a polymer) and reinforced concrete (steel or other fibers in cement). The beauty of composites is the synergy—the whole material gains qualities that none of the components have on their own.

The other terms point to different ideas: micro encapsulation is about enclosing substances to protect or control their release; thermochromic ink changes color with temperature; and QTC, or Quantum Tunneling Composite, is a material whose electrical resistance changes under pressure. None of these describe the general idea of combining materials to form a new material with enhanced properties in the way composites do.