Explain why some time after meal the blood glucose concentration falls below its current level??? Someone please help!

1. desertification

2. captive breeding

3. black rhinoceros

4. renewable resources

explanation:

mark brainliest!

"a.) well–developed vascular system."

they had the law tat factories that produces smoke cannot be built near residential buildings.

building of proper sewage system was done to ensure that the waste is carried away from the humans so that they do not get diseases from it.

also they built water systems to provide water in those areas which are drought prone.