C because cellular respiration uses combine oxygen and other toxic waste.
Answer:
Calcitonin stimulates the kidneys to absorb calcium when calcium levels are too low, while parathyroid hormone stimulates the kidneys to excrete calcium when calcium levels are too high.
Explanation:
Your answer is burning gasoline. if you think about it, none of the rest of the answers really involve chemicals. ice isnt known as a chemical, and so isnt glass. and if your dent a bumper, it doesnt make sense to add it as a chemical change. so your answer is burning gasoline. hope this helps.