B is unsustainable as this is a practice of intensive farming usually conducted indoors, and is resource and energy expensive. C is unsustainable because groundwater is a limited resource and groundwater can take 1000s of years to be recharged. D is unsustainable as this involves moving water across vast distances and is expensive and ecologically damaging. A is sustainable as drought-resistant plants would in the long run use less water.
I think carbon dioxide would be a correct answer, but you didn't post the possible answers
Answer:
The Ozone Layer would repair
Explanation:
CFC's are chlorofluorocarbons. They generally eat the ozone layer. It stands to reason that a reduction in CFC's would reduce the depletion of the ozone layer allowing it to slowly repair itself through natural processes.
Labeo = gills
Dolphin= pisces
Tadpole = hibernation
snake= internal fertilization
Eagle = aerial mode of life
Human = mammals