Problem:OPTIONS:
- humans
- crop yeilds
- food safety
- health
- Cooking
- Animal survival
- recipe requirements
- farm production

You are presented with the quiz "killing microorganisms in food is important to" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "irradiating food can be used to kill existing microorganisms in the food" and "food irradiation offers a solution for addressing the growing concerns associated with food safety". So, what's the best answer to the question?
****
A: food safety

Problem:OPTIONS:
- Proteins
- food
- DNA
- nutrients
- energy
- Light
- bamboo
- sunlight

You are presented with the quiz "What do all living things require in order to reproduce?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "living things all require energy for survival" and "energy is used for survival and reproduction". So, what's the best answer to the question?
****
A: energy

Problem:OPTIONS:
- an exoskeleton
- legs
- Bodily water
- Damaged hearing
- kinetic energy
- a backbone
- Energy
- backs

You are presented with the quiz "What don't arthropods have?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "arthropods are the largest phylum of invertebrates" and "invertebrates are animals without a backbone". So, what's the best answer to the question?
****
A: a backbone

Problem:OPTIONS:
- flooding
- Pesticides
- erosion
- contamination
- competition
- Pollution
- sulfur dioxide
- deforestation

You are presented with the quiz "Water quality can be negatively effected by what? " But you don't know the answer, so you turn to your teacher to ask for hints. He says that "acid rain has a negative impact on water quality" and "sulfur dioxide causes acid rain". So, what's the best answer to the question?
****
A:
sulfur dioxide