Choose the sentence in this excerpt that provides evidence of tangible results of chemistry research.
1. Many chemists and materials scientists work in basic and applied research.
2. In basic research, chemists investigate the properties, composition, and structure of matter.
3. They also experiment with combinations of elements and the ways in which they interact.
4. In applied research, chemists investigate possible new products and ways to improve existing ones.
5. Chemistry research has led to the discovery and development of new and improved drugs, plastics, cleaners, and thousands of other products.
The correct sentence is:
5. Chemistry research has led to the discovery and development of new and improved drugs, plastics, cleaners, and thousands of other products.
Explanation: This sentence provides tangible results of chemistry research by specifically mentioning the new and improved products that have been developed as a result of this research, illustrating the practical applications and benefits of chemistry in everyday life.