Answer:
A
Explanation:
Tilling agitates the topsoil and removes ‘unnecessary’ vegetation so the main crop can grow without competition. Tilling improves soil aeration and drainage for plants to grow well. Nonetheless, it can lead to other consequences such as soil erosion because it loosens the soil and makes it easy to be carried away by wind and water.
Animals were used for food.!
Humans can respire aerobically and anaerobically. Pyruvate and ATP are products both aerobic cell respiration and anaerobic cell respiration in Humans.
The answer should be 4) as it is known that uv radiation might have an effect on dna, thus causing mutations such as skin cancer in humans.
