C because he is making a hypothesis that coloration which is the independent variable is making the change.
They are known as polar molecules. For example, water has regions varying in electric charge. Therefore, its one end is positively charged, and another end is negatively charged.
All 3 farming techniques are methods of soil conservation.
Contour plowing is used to stop water from flowing directly down slope to prevent gullying.
Terracing is used to slow the amount of runoff, and prevents rapid soil erosion.
Strip Cropping is when farmers plant plants in alternating bands to stop soil erosion.
