Question: A student provides the following directions for brushing teeth: • Turn on the water. • Fill the glass with water and leave the water running. • Put toothpaste on the toothbrush. • Brush for two minutes. • Rinse mouth with the water from the glass. • Rinse the toothbrush with the running water. • Turn off the water. Which change in these directions would conserve the most water?

  Options: 
 A. Brush for three minutes.
 B. Turn the water off before brushing.
 C. Rinse mouth with the running water.
 D. Use less toothpaste on the toothbrush.
Answer: B